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math-010601
Foundations of Calculus: Area vs Antiderivative
6
Start by stating any domain restrictions: Compute the definite integral $$\int_0^23 (7x+(38))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=7x+(38)$ is a line on $[0,23]$.", "Step 2: The integral equals the signed area: rectangle from...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\frac{5451}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Su...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Takeaway: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010602
Calculus: Derivatives — Difference Quotient
6
Carefully track domains: Let $f(x)=10x^2+(-10)x$. (a) Compute $f'(6)$ using differentiation rules. (b) Compute $f'(6)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justi...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=10(a+h)^2+(-10)(a+h)=10(a^2+2ah+h^2)+(-10)a+(-10)h$.",...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{110}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=10,n=-10,a=6$ both give 110.", "robustness_analysis": "Sensitivity analysis: The rule-b...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010603
Calculus: Derivatives — Power Rule
6
Write the solution set clearly: Let $f(x)=-2x^2+(16)x$. (a) Compute $f'(4)$ using differentiation rules. (b) Compute $f'(4)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-2)x+(16)=-4x+(16)$.", "Step 2: Substitute $x=4$ to get $f'(4)=-4(4)+(16)=0$.", "Final step: Therefore \\boxed{0}." ], "final_answer": "\\...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{0}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-2,n=16,a=4$ both give 0.", "robustness_analysis": "Generality note: The rule-based metho...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010604
Calculus: Derivatives — Difference Quotient
6
Do not skip justification steps: Let $f(x)=1x^2+(-12)x$. (a) Compute $f'(14)$ using differentiation rules. (b) Compute $f'(14)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explici...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=1(a+h)^2+(-12)(a+h)=1(a^2+2ah+h^2)+(-12)a+(-12)h$.", ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{16}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=1,n=-12,a=14$ both give 16.", "robustness_analysis": "If the problem we...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010605
Calculus: Differentiation — Cross-Validation
6
Solve and then verify: Let $f(x)=-4x^2+(24)x$. (a) Compute $f'(13)$ using differentiation rules. (b) Compute $f'(13)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justif...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-4(a+h)^2+(24)(a+h)=-4(a^2+2ah+h^2)+(24)a+(24)h$.", ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-80}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-4,n=24,a=13$ both give -80.", "robustness_analysis": "If the problem ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-80}$.)
math-010606
Calculus: Integrals — Linear Functions
6
Start by stating any domain restrictions: Compute the definite integral $$\int_0^17 (1x+(-39))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signe...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{1}{2}x^2+(-39)x$ since $F'(x)=1x+(-39)$.", "Step 2: By FTC, $\\int_0^17 (1x+(-39))dx = F(17)-F(0)$.", "Final step: $F(17)-F(0)=...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\frac{-1037}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=1,q=-39,t=1...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010607
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Give a fully justified solution: Let $f(x)=7x^2+(5)x$. (a) Compute $f'(-9)$ using differentiation rules. (b) Compute $f'(-9)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitl...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(7)x+(5)=14x+(5)$.", "Step 2: Substitute $x=-9$ to get $f'(-9)=14(-9)+(5)=-121$.", "Final step: Therefore \\boxed{-121}." ], "final_answer"...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-121}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=7,n=5,a=-9$ both give -121.", "robustness_analysis": "If the problem were perturbed: T...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010608
Calculus: Derivatives — Power Rule
6
Provide a rigorous solution: Let $f(x)=11x^2+(-10)x$. (a) Compute $f'(12)$ using differentiation rules. (b) Compute $f'(12)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(11)x+(-10)=22x+(-10)$.", "Step 2: Substitute $x=12$ to get $f'(12)=22(12)+(-10)=254$.", "Final step: Therefore \\boxed{254}." ], "final_an...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{254}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=11,n=-10,a=12$ both give 254.", "robustness_analysis": "Sensitivity an...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{254}$.)
math-010609
Calculus: Integrals — Signed Area Interpretation
6
Work this out carefully: Compute the definite integral $$\int_0^6 (10x+(-14))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles t...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=10x+(-14)$ is a line on $[0,6]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{96}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=10,q...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Takeaway: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{96}$.)
math-010610
Calculus: Derivatives — Difference Quotient
6
Indicate where a theorem is used: Let $f(x)=12x^2+(2)x$. (a) Compute $f'(15)$ using differentiation rules. (b) Compute $f'(15)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explici...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=12(a+h)^2+(2)(a+h)=12(a^2+2ah+h^2)+(2)a+(2)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{362}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=12,n=2,a=15$ both give 362.", "robustness_analysis": "Sensitivity analysis: The rule-ba...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{362}$.)
math-010611
Calculus: Integrals — Fundamental Theorem of Calculus
6
Try to avoid pattern-matching; explain why: Compute the definite integral $$\int_0^24 (-15x+(1))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'sig...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-15}{2}x^2+(1)x$ since $F'(x)=-15x+(1)$.", "Step 2: By FTC, $\\int_0^24 (-15x+(1))dx = F(24)-F(0)$.", "Final step: $F(24)-F(0)=...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-4296}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-15,q=1,t=24$ yields -42...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-4296}$.)
math-010612
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Problem: Let $f(x)=8x^2+(-10)x$. (a) Compute $f'(-18)$ using differentiation rules. (b) Compute $f'(-18)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(8)x+(-10)=16x+(-10)$.", "Step 2: Substitute $x=-18$ to get $f'(-18)=16(-18)+(-10)=-298$.", "Final step: Therefore \\boxed{-298}." ], "fina...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-298}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=8,n=-10,a=-18$ both give -298.", "robustness_analysis": "Generality note: The rule-based met...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-298}$.)
math-010613
Calculus: Integrals — Fundamental Theorem of Calculus
6
Prompt: Compute the definite integral $$\int_0^40 (-3x+(-6))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when the ...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-3}{2}x^2+(-6)x$ since $F'(x)=-3x+(-6)$.", "Step 2: By FTC, $\\int_0^40 (-3x+(-6))dx = F(40)-F(0)$.", "Final step: $F(40)-F(0)=...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-2640}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-3,q=-6,t=40$ yiel...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Takeaway: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-2640}$.)
math-010614
Foundations of Calculus: Derivative Definition
6
Do not skip justification steps: Let $f(x)=4x^2+(-26)x$. (a) Compute $f'(-8)$ using differentiation rules. (b) Compute $f'(-8)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explici...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(4)x+(-26)=8x+(-26)$.", "Step 2: Substitute $x=-8$ to get $f'(-8)=8(-8)+(-26)=-90$.", "Final step: Therefore \\boxed{-90}." ], "final_answe...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-90}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=4,n=-26,a=-8$ both give -90.", "robustness_analysis": "Robustness note...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-90}$.)
math-010615
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Solve with verification: Let $f(x)=-1x^2+(12)x$. (a) Compute $f'(-14)$ using differentiation rules. (b) Compute $f'(-14)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly ju...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-1)x+(12)=-2x+(12)$.", "Step 2: Substitute $x=-14$ to get $f'(-14)=-2(-14)+(12)=40$.", "Final step: Therefore \\boxed{40}." ], "final_answ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{40}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-1,n=12,a=-14$ both give 40.", "robustness_analysis": "Robustn...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010616
Foundations of Calculus: Area vs Antiderivative
6
Checkpoint: Compute the definite integral $$\int_0^12 (-3x+(7))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when t...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-3}{2}x^2+(7)x$ since $F'(x)=-3x+(7)$.", "Step 2: By FTC, $\\int_0^12 (-3x+(7))dx = F(12)-F(0)$.", "Final step: $F(12)-F(0)=\\f...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-132}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-3...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-132}$.)
math-010617
Calculus: Derivatives — Power Rule
6
Try to avoid pattern-matching; explain why: Let $f(x)=-8x^2+(19)x$. (a) Compute $f'(-1)$ using differentiation rules. (b) Compute $f'(-1)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-8(a+h)^2+(19)(a+h)=-8(a^2+2ah+h^2)+(19)a+(19)h$.", ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{35}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-8,n=19,a=-1$ both give 35.", "robustness_analysis": "Generali...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{35}$.)
math-010618
Calculus: Derivatives — Difference Quotient
6
Prompt: Let $f(x)=-2x^2+(24)x$. (a) Compute $f'(16)$ using differentiation rules. (b) Compute $f'(16)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling $h...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-2(a+h)^2+(24)(a+h)=-2(a^2+2ah+h^2)+(24)a+(24)h$.", ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-40}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-2,n=24,a=16$ both give -40.", "robustness_analysis": "Genera...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010619
Foundations of Calculus: Area vs Antiderivative
6
Indicate where a theorem is used: Compute the definite integral $$\int_0^25 (7x+(15))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' h...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{7}{2}x^2+(15)x$ since $F'(x)=7x+(15)$.", "Step 2: By FTC, $\\int_0^25 (7x+(15))dx = F(25)-F(0)$.", "Final step: $F(25)-F(0)=\\f...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\frac{5125}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Su...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{\frac{5125}$.)
math-010620
Foundations of Calculus: Derivative Definition
6
Compute the requested quantity: Let $f(x)=11x^2+(27)x$. (a) Compute $f'(-20)$ using differentiation rules. (b) Compute $f'(-20)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explic...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(11)x+(27)=22x+(27)$.", "Step 2: Substitute $x=-20$ to get $f'(-20)=22(-20)+(27)=-413$.", "Final step: Therefore \\boxed{-413}." ], "final_...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-413}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=11,n=27,a=-20$ both give -413.", "robustness_analysis": "If ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010621
Calculus: Integrals — Exact Arithmetic
6
Give a fully justified solution: Compute the definite integral $$\int_0^11 (14x+(5))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' ha...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{14}{2}x^2+(5)x$ since $F'(x)=14x+(5)$.", "Step 2: By FTC, $\\int_0^11 (14x+(5))dx = F(11)-F(0)$.", "Final step: $F(11)-F(0)=\\f...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{902}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=14,...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010622
Calculus: Integrals — Exact Arithmetic
6
Compute the requested quantity: Compute the definite integral $$\int_0^27 (8x+(4))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' hand...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{8}{2}x^2+(4)x$ since $F'(x)=8x+(4)$.", "Step 2: By FTC, $\\int_0^27 (8x+(4))dx = F(27)-F(0)$.", "Final step: $F(27)-F(0)=\\frac...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{3024}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=8,...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010623
Calculus: Derivatives — Power Rule
6
Solve and then verify: Let $f(x)=5x^2+(-5)x$. (a) Compute $f'(11)$ using differentiation rules. (b) Compute $f'(11)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(5)x+(-5)=10x+(-5)$.", "Step 2: Substitute $x=11$ to get $f'(11)=10(11)+(-5)=105$.", "Final step: Therefore \\boxed{105}." ], "final_answer...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{105}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=5,n=-5,a=11$ both give 105.", "robustness_analysis": "Robustness note: The rule-based method ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{105}$.)
math-010624
Calculus: Integrals — Exact Arithmetic
6
Solve (and briefly cross-validate): Compute the definite integral $$\int_0^14 (13x+(37))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=13x+(37)$ is a line on $[0,14]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1792}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=13,q=37,t=14$ yield...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010625
Calculus: Integrals — Linear Functions
6
Solve and include a self-check: Compute the definite integral $$\int_0^17 (-4x+(-6))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' ha...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-4x+(-6)$ is a line on $[0,17]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-680}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-4,q=-6,t=17$ yields -680...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-680}$.)
math-010626
Calculus: Derivatives — Power Rule
6
Work carefully and justify each inference: Let $f(x)=-4x^2+(17)x$. (a) Compute $f'(-11)$ using differentiation rules. (b) Compute $f'(-11)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-4(a+h)^2+(17)(a+h)=-4(a^2+2ah+h^2)+(17)a+(17)h$.", ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{105}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-4,n=17,a=-11$ both give 105.", "robustness_analysis": "Generality note: The rule-based metho...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010627
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Carefully track domains: Let $f(x)=-4x^2+(22)x$. (a) Compute $f'(-1)$ using differentiation rules. (b) Compute $f'(-1)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly just...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-4)x+(22)=-8x+(22)$.", "Step 2: Substitute $x=-1$ to get $f'(-1)=-8(-1)+(22)=30$.", "Final step: Therefore \\boxed{30}." ], "final_answer"...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{30}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-4,n=22,a=-1$ both give 30.", "robustness_analysis": "Sensitivity analy...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010628
Foundations of Calculus: Area vs Antiderivative
6
Use two approaches if possible: Compute the definite integral $$\int_0^31 (-9x+(38))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' ha...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-9x+(38)$ is a line on $[0,31]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\frac{-6293}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituti...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{\frac{-6293}$.)
math-010629
Calculus: Derivatives — Difference Quotient
6
Try to avoid pattern-matching; explain why: Let $f(x)=2x^2+(-18)x$. (a) Compute $f'(-6)$ using differentiation rules. (b) Compute $f'(-6)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=2(a+h)^2+(-18)(a+h)=2(a^2+2ah+h^2)+(-18)a+(-18)h$.", ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-42}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=2,n=-18,a=-6$ both give -42.", "robustness_analysis": "Generality note: The rule-based method...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-42}$.)
math-010630
Calculus: Differentiation — Cross-Validation
6
Give reasoning, not just computation: Let $f(x)=-5x^2+(12)x$. (a) Compute $f'(1)$ using differentiation rules. (b) Compute $f'(1)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and expl...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-5(a+h)^2+(12)(a+h)=-5(a^2+2ah+h^2)+(12)a+(12)h$.", ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{2}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-5,n=12,a=1$ both give 2.", "robustness_analysis": "Robustness ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{2}$.)
math-010631
Calculus: Differentiation — Cross-Validation
6
Use two approaches if possible: Let $f(x)=11x^2+(-3)x$. (a) Compute $f'(10)$ using differentiation rules. (b) Compute $f'(10)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicit...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=11(a+h)^2+(-3)(a+h)=11(a^2+2ah+h^2)+(-3)a+(-3)h$.", ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{217}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=11,n=-3,a=10$ both give 217.", "robustness_analysis": "Generality note...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{217}$.)
math-010632
Calculus: Differentiation — Cross-Validation
6
Make each step logically reversible (or explain if not): Let $f(x)=-7x^2+(-17)x$. (a) Compute $f'(-16)$ using differentiation rules. (b) Compute $f'(-16)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-7)x+(-17)=-14x+(-17)$.", "Step 2: Substitute $x=-16$ to get $f'(-16)=-14(-16)+(-17)=207$.", "Final step: Therefore \\boxed{207}." ], "fin...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{207}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-7,n=-17,a=-16$ both give 207.", "robustness_analysis": "If the proble...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{207}$.)
math-010633
Calculus: Integrals — Fundamental Theorem of Calculus
6
Keep the final answer in boxed form: Compute the definite integral $$\int_0^17 (-15x+(27))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed ar...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-15x+(27)$ is a line on $[0,17]$.", "Step 2: The integral equals the signed area: rectangle fr...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\frac{-3417}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-15,q=27,t=17$ yi...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010634
Calculus: Differentiation — Cross-Validation
6
Prompt: Let $f(x)=10x^2+(-7)x$. (a) Compute $f'(-15)$ using differentiation rules. (b) Compute $f'(-15)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling ...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(10)x+(-7)=20x+(-7)$.", "Step 2: Substitute $x=-15$ to get $f'(-15)=20(-15)+(-7)=-307$.", "Final step: Therefore \\boxed{-307}." ], "final_...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-307}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=10,n=-7,a=-15$ both give -307.", "robustness_analysis": "If ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-307}$.)
math-010635
Foundations of Calculus: Derivative Definition
6
Warm-up: Let $f(x)=-6x^2+(-1)x$. (a) Compute $f'(-4)$ using differentiation rules. (b) Compute $f'(-4)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling $...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-6)x+(-1)=-12x+(-1)$.", "Step 2: Substitute $x=-4$ to get $f'(-4)=-12(-4)+(-1)=47$.", "Final step: Therefore \\boxed{47}." ], "final_answe...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{47}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-6,n=-1,a=-4$ both give 47.", "robustness_analysis": "If the problem were perturbed: The rule-...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{47}$.)
math-010636
Calculus: Integrals — Linear Functions
6
Work this out carefully: Compute the definite integral $$\int_0^9 (-11x+(38))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles t...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-11x+(38)$ is a line on $[0,9]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\frac{-207}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-11,q=38,t=9...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010637
Calculus: Integrals — Linear Functions
6
Where appropriate, name the theorem you use: Compute the definite integral $$\int_0^18 (-7x+(-27))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 's...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-7}{2}x^2+(-27)x$ since $F'(x)=-7x+(-27)$.", "Step 2: By FTC, $\\int_0^18 (-7x+(-27))dx = F(18)-F(0)$.", "Final step: $F(18)-F(...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-1620}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-1620}$.)
math-010638
Calculus: Integrals — Fundamental Theorem of Calculus
6
Question: Compute the definite integral $$\int_0^24 (-12x+(-9))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when t...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-12}{2}x^2+(-9)x$ since $F'(x)=-12x+(-9)$.", "Step 2: By FTC, $\\int_0^24 (-12x+(-9))dx = F(24)-F(0)$.", "Final step: $F(24)-F(...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-3672}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-12,q=-9,t=24$ yields -3...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-3672}$.)
math-010639
Calculus: Derivatives — Power Rule
6
Carefully track domains: Let $f(x)=6x^2+(-5)x$. (a) Compute $f'(5)$ using differentiation rules. (b) Compute $f'(5)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=6(a+h)^2+(-5)(a+h)=6(a^2+2ah+h^2)+(-5)a+(-5)h$.", ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{55}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=6,n=-5,a=5$ both give 55.", "robustness_analysis": "If the pro...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{55}$.)
math-010640
Calculus: Derivatives — Power Rule
6
Work carefully and justify each inference: Let $f(x)=-6x^2+(23)x$. (a) Compute $f'(-16)$ using differentiation rules. (b) Compute $f'(-16)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-6(a+h)^2+(23)(a+h)=-6(a^2+2ah+h^2)+(23)a+(23)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{215}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-6,n=23,a=-16$ both give 215.", "robustness_analysis": "Sensitivity analysis: The rule-...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{215}$.)
math-010641
Calculus: Derivatives — Power Rule
6
Where appropriate, name the theorem you use: Let $f(x)=-2x^2+(-14)x$. (a) Compute $f'(10)$ using differentiation rules. (b) Compute $f'(10)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefull...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-2(a+h)^2+(-14)(a+h)=-2(a^2+2ah+h^2)+(-14)a+(-14)h$.",...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-54}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-2,n=-14,a=10$ both give -54.", "robustness_analysis": "Sensi...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-54}$.)
math-010642
Foundations of Calculus: Area vs Antiderivative
6
Write the solution set clearly: Compute the definite integral $$\int_0^14 (7x+(3))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' hand...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{7}{2}x^2+(3)x$ since $F'(x)=7x+(3)$.", "Step 2: By FTC, $\\int_0^14 (7x+(3))dx = F(14)-F(0)$.", "Final step: $F(14)-F(0)=\\frac...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{728}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=7,q=3,t=14$ yields 7...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{728}$.)
math-010643
Calculus: Integrals — Fundamental Theorem of Calculus
6
Track units/moduli carefully: Compute the definite integral $$\int_0^18 (-8x+(27))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' hand...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-8x+(27)$ is a line on $[0,18]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-810}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitut...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-810}$.)
math-010644
Calculus: Integrals — Signed Area Interpretation
6
Derive the result step-by-step: Compute the definite integral $$\int_0^20 (-11x+(9))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' ha...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-11}{2}x^2+(9)x$ since $F'(x)=-11x+(9)$.", "Step 2: By FTC, $\\int_0^20 (-11x+(9))dx = F(20)-F(0)$.", "Final step: $F(20)-F(0)=...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-2020}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitu...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-2020}$.)
math-010645
Calculus: Integrals — Signed Area Interpretation
6
Explain why your operations are valid: Compute the definite integral $$\int_0^14 (-13x+(-11))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-13}{2}x^2+(-11)x$ since $F'(x)=-13x+(-11)$.", "Step 2: By FTC, $\\int_0^14 (-13x+(-11))dx = F(14)-F(0)$.", "Final step: $F(14)...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-1428}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-1428}$.)
math-010646
Calculus: Integrals — Exact Arithmetic
6
Give a fully justified solution: Compute the definite integral $$\int_0^8 (1x+(2))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' hand...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=1x+(2)$ is a line on $[0,8]$.", "Step 2: The integral equals the signed area: rectangle from t...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{48}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=1,q=2,t=8$ yields 48.", "...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{48}$.)
math-010647
Calculus: Differentiation — Cross-Validation
6
Indicate where a theorem is used: Let $f(x)=9x^2+(13)x$. (a) Compute $f'(-12)$ using differentiation rules. (b) Compute $f'(-12)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and expli...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(9)x+(13)=18x+(13)$.", "Step 2: Substitute $x=-12$ to get $f'(-12)=18(-12)+(13)=-203$.", "Final step: Therefore \\boxed{-203}." ], "final_a...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-203}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=9,n=13,a=-12$ both give -203.", "robustness_analysis": "Generality note: The rule-base...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-203}$.)
math-010648
Calculus: Integrals — Fundamental Theorem of Calculus
6
Checkpoint: Compute the definite integral $$\int_0^5 (7x+(-24))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when t...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{7}{2}x^2+(-24)x$ since $F'(x)=7x+(-24)$.", "Step 2: By FTC, $\\int_0^5 (7x+(-24))dx = F(5)-F(0)$.", "Final step: $F(5)-F(0)=\\f...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\frac{-65}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=7,q=-24,t=5$ yields...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010649
Calculus: Differentiation — Cross-Validation
6
Work carefully and justify each inference: Let $f(x)=-1x^2+(-30)x$. (a) Compute $f'(-3)$ using differentiation rules. (b) Compute $f'(-3)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-1(a+h)^2+(-30)(a+h)=-1(a^2+2ah+h^2)+(-30)a+(-30)h$.",...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-24}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-1,n=-30,a=-3$ both give -24.", "robustness_analysis": "Sensitivity an...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-24}$.)
math-010650
Calculus: Integrals — Exact Arithmetic
6
Question: Compute the definite integral $$\int_0^39 (9x+(35))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when the...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=9x+(35)$ is a line on $[0,39]$.", "Step 2: The integral equals the signed area: rectangle from...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\frac{16419}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=9,q=35,t=39...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{\frac{16419}$.)
math-010651
Calculus: Derivatives — Power Rule
6
Answer using clear logical steps: Let $f(x)=-9x^2+(-29)x$. (a) Compute $f'(18)$ using differentiation rules. (b) Compute $f'(18)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and expli...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-9)x+(-29)=-18x+(-29)$.", "Step 2: Substitute $x=18$ to get $f'(18)=-18(18)+(-29)=-353$.", "Final step: Therefore \\boxed{-353}." ], "fina...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-353}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-9,n=-29,a=18$ both give -353.", "robustness_analysis": "Generality note: The rule-based met...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-353}$.)
math-010652
Foundations of Calculus: Derivative Definition
6
Checkpoint: Let $f(x)=-6x^2+(28)x$. (a) Compute $f'(-10)$ using differentiation rules. (b) Compute $f'(-10)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancell...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-6(a+h)^2+(28)(a+h)=-6(a^2+2ah+h^2)+(28)a+(28)h$.", ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{148}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-6,n=28,a=-10$ both give 148.", "robustness_analysis": "Generality not...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010653
Calculus: Derivatives — Difference Quotient
6
Use two approaches if possible: Let $f(x)=-10x^2+(24)x$. (a) Compute $f'(-16)$ using differentiation rules. (b) Compute $f'(-16)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and expli...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-10)x+(24)=-20x+(24)$.", "Step 2: Substitute $x=-16$ to get $f'(-16)=-20(-16)+(24)=344$.", "Final step: Therefore \\boxed{344}." ], "final...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{344}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-10,n=24,a=-16$ both give 344.", "robustness_analysis": "Robustness note: The rule-based meth...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{344}$.)
math-010654
Foundations of Calculus: Derivative Definition
6
Complete the analysis: Let $f(x)=-1x^2+(13)x$. (a) Compute $f'(3)$ using differentiation rules. (b) Compute $f'(3)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-1(a+h)^2+(13)(a+h)=-1(a^2+2ah+h^2)+(13)a+(13)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{7}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-1,n=13,a=3$ both give 7.", "robustness_analysis": "If the problem were perturbed: The ru...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{7}$.)
math-010655
Calculus: Derivatives — Difference Quotient
6
Carefully track domains: Let $f(x)=7x^2+(18)x$. (a) Compute $f'(-16)$ using differentiation rules. (b) Compute $f'(-16)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly jus...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(7)x+(18)=14x+(18)$.", "Step 2: Substitute $x=-16$ to get $f'(-16)=14(-16)+(18)=-206$.", "Final step: Therefore \\boxed{-206}." ], "final_a...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-206}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=7,n=18,a=-16$ both give -206.", "robustness_analysis": "Sensitivity analysis: The rule...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-206}$.)
math-010656
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Solve and sanity-check: Let $f(x)=-5x^2+(4)x$. (a) Compute $f'(-10)$ using differentiation rules. (b) Compute $f'(-10)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly just...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-5(a+h)^2+(4)(a+h)=-5(a^2+2ah+h^2)+(4)a+(4)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{104}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-5,n=4,a=-10$ both give 104.", "robustness_analysis": "Robustness note: The rule-based ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{104}$.)
math-010657
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Answer with a short justification: Let $f(x)=-1x^2+(-7)x$. (a) Compute $f'(-20)$ using differentiation rules. (b) Compute $f'(-20)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and exp...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-1(a+h)^2+(-7)(a+h)=-1(a^2+2ah+h^2)+(-7)a+(-7)h$.", ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{33}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-1,n=-7,a=-20$ both give 33.", "robustness_analysis": "Sensiti...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{33}$.)
math-010658
Calculus: Differentiation — Cross-Validation
6
Derive the result step-by-step: Let $f(x)=5x^2+(25)x$. (a) Compute $f'(7)$ using differentiation rules. (b) Compute $f'(7)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=5(a+h)^2+(25)(a+h)=5(a^2+2ah+h^2)+(25)a+(25)h$.", ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{95}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=5,n=25,a=7$ both give 95.", "robustness_analysis": "Sensitivit...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{95}$.)
math-010659
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Prompt: Let $f(x)=-3x^2+(-9)x$. (a) Compute $f'(-10)$ using differentiation rules. (b) Compute $f'(-10)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-3(a+h)^2+(-9)(a+h)=-3(a^2+2ah+h^2)+(-9)a+(-9)h$.", ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{51}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-3,n=-9,a=-10$ both give 51.", "robustness_analysis": "Sensitivity anal...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{51}$.)
math-010660
Calculus: Differentiation — Cross-Validation
6
Answer using clear logical steps: Let $f(x)=9x^2+(4)x$. (a) Compute $f'(7)$ using differentiation rules. (b) Compute $f'(7)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=9(a+h)^2+(4)(a+h)=9(a^2+2ah+h^2)+(4)a+(4)h$.", "...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{130}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=9,n=4,a=7$ both give 130.", "robustness_analysis": "Generality note: The rule-based method is...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{130}$.)
math-010661
Foundations of Calculus: Area vs Antiderivative
6
Use two approaches if possible: Compute the definite integral $$\int_0^7 (3x+(29))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' hand...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{3}{2}x^2+(29)x$ since $F'(x)=3x+(29)$.", "Step 2: By FTC, $\\int_0^7 (3x+(29))dx = F(7)-F(0)$.", "Final step: $F(7)-F(0)=\\frac...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\frac{553}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=3,q=29,t=7$ y...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{\frac{553}$.)
math-010662
Calculus: Integrals — Exact Arithmetic
6
Exercise: Compute the definite integral $$\int_0^10 (-10x+(3))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when th...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-10x+(3)$ is a line on $[0,10]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-470}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-1...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-470}$.)
math-010663
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Work carefully and justify each inference: Let $f(x)=-4x^2+(-16)x$. (a) Compute $f'(-19)$ using differentiation rules. (b) Compute $f'(-19)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefull...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-4)x+(-16)=-8x+(-16)$.", "Step 2: Substitute $x=-19$ to get $f'(-19)=-8(-19)+(-16)=136$.", "Final step: Therefore \\boxed{136}." ], "final...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{136}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-4,n=-16,a=-19$ both give 136.", "robustness_analysis": "Sensitivity analysis: The rule...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010664
Calculus: Integrals — Fundamental Theorem of Calculus
6
Proceed methodically: Compute the definite integral $$\int_0^34 (9x+(-7))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the c...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=9x+(-7)$ is a line on $[0,34]$.", "Step 2: The integral equals the signed area: rectangle from...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{4964}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=9,q=-7,t=34$ yields 4964....
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Takeaway: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010665
Foundations of Calculus: Area vs Antiderivative
6
Find the exact value: Compute the definite integral $$\int_0^2 (-9x+(-24))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the ...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-9}{2}x^2+(-24)x$ since $F'(x)=-9x+(-24)$.", "Step 2: By FTC, $\\int_0^2 (-9x+(-24))dx = F(2)-F(0)$.", "Final step: $F(2)-F(0)=...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-66}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-9,q=-24,t=2$ yields -66."...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-66}$.)
math-010666
Calculus: Integrals — Fundamental Theorem of Calculus
6
Question: Compute the definite integral $$\int_0^23 (3x+(28))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when the...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=3x+(28)$ is a line on $[0,23]$.", "Step 2: The integral equals the signed area: rectangle from...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\frac{2875}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=3,q=28,t=23$ yield...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010667
Calculus: Differentiation — Cross-Validation
6
Complete the analysis: Let $f(x)=-10x^2+(-13)x$. (a) Compute $f'(0)$ using differentiation rules. (b) Compute $f'(0)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justif...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-10(a+h)^2+(-13)(a+h)=-10(a^2+2ah+h^2)+(-13)a+(-13)h$....
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-13}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-10,n=-13,a=0$ both give -13.", "robustness_analysis": "Generality note: The rule-based...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010668
Foundations of Calculus: Derivative Definition
6
Solve and sanity-check: Let $f(x)=11x^2+(-9)x$. (a) Compute $f'(-18)$ using differentiation rules. (b) Compute $f'(-18)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly jus...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=11(a+h)^2+(-9)(a+h)=11(a^2+2ah+h^2)+(-9)a+(-9)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-405}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=11,n=-9,a=-18$ both give -405.", "robustness_analysis": "Robustness note: The rule-bas...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-405}$.)
math-010669
Foundations of Calculus: Area vs Antiderivative
6
Solve and justify each step: Compute the definite integral $$\int_0^3 (-9x+(-33))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handl...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-9}{2}x^2+(-33)x$ since $F'(x)=-9x+(-33)$.", "Step 2: By FTC, $\\int_0^3 (-9x+(-33))dx = F(3)-F(0)$.", "Final step: $F(3)-F(0)=...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\frac{-279}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitutin...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{\frac{-279}$.)
math-010670
Foundations of Calculus: Area vs Antiderivative
6
Checkpoint: Compute the definite integral $$\int_0^21 (-5x+(21))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when ...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-5}{2}x^2+(21)x$ since $F'(x)=-5x+(21)$.", "Step 2: By FTC, $\\int_0^21 (-5x+(21))dx = F(21)-F(0)$.", "Final step: $F(21)-F(0)=...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\frac{-1323}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). S...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010671
Calculus: Differentiation — Cross-Validation
6
Make each step logically reversible (or explain if not): Let $f(x)=10x^2+(26)x$. (a) Compute $f'(-11)$ using differentiation rules. (b) Compute $f'(-11)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=10(a+h)^2+(26)(a+h)=10(a^2+2ah+h^2)+(26)a+(26)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-194}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=10,n=26,a=-11$ both give -194.", "robustness_analysis": "Generality note: The rule-bas...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-194}$.)
math-010672
Calculus: Integrals — Signed Area Interpretation
6
Prompt: Compute the definite integral $$\int_0^5 (10x+(22))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when the l...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{10}{2}x^2+(22)x$ since $F'(x)=10x+(22)$.", "Step 2: By FTC, $\\int_0^5 (10x+(22))dx = F(5)-F(0)$.", "Final step: $F(5)-F(0)=\\f...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{235}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=10,...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010673
Foundations of Calculus: Derivative Definition
6
Compute the requested quantity: Let $f(x)=-10x^2+(19)x$. (a) Compute $f'(-5)$ using differentiation rules. (b) Compute $f'(-5)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explici...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-10)x+(19)=-20x+(19)$.", "Step 2: Substitute $x=-5$ to get $f'(-5)=-20(-5)+(19)=119$.", "Final step: Therefore \\boxed{119}." ], "final_an...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{119}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-10,n=19,a=-5$ both give 119.", "robustness_analysis": "If the problem were perturbed: The ru...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010674
Calculus: Differentiation — Cross-Validation
6
Complete the analysis: Let $f(x)=-2x^2+(24)x$. (a) Compute $f'(-14)$ using differentiation rules. (b) Compute $f'(-14)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly just...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-2)x+(24)=-4x+(24)$.", "Step 2: Substitute $x=-14$ to get $f'(-14)=-4(-14)+(24)=80$.", "Final step: Therefore \\boxed{80}." ], "final_answ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{80}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-2,n=24,a=-14$ both give 80.", "robustness_analysis": "Generality note: The rule-based method ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010675
Calculus: Integrals — Fundamental Theorem of Calculus
6
Challenge: Compute the definite integral $$\int_0^23 (12x+(-12))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when ...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{12}{2}x^2+(-12)x$ since $F'(x)=12x+(-12)$.", "Step 2: By FTC, $\\int_0^23 (12x+(-12))dx = F(23)-F(0)$.", "Final step: $F(23)-F(...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{2898}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=12,q=-12,t=23$ yields 289...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{2898}$.)
math-010676
Calculus: Integrals — Linear Functions
6
Question: Compute the definite integral $$\int_0^32 (7x+(-24))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when th...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{7}{2}x^2+(-24)x$ since $F'(x)=7x+(-24)$.", "Step 2: By FTC, $\\int_0^32 (7x+(-24))dx = F(32)-F(0)$.", "Final step: $F(32)-F(0)=...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{2816}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=7,q=-24,t=32$ yields 2816...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010677
Calculus: Integrals — Linear Functions
6
Give a theorem-based solution: Compute the definite integral $$\int_0^14 (-15x+(-29))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' h...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-15x+(-29)$ is a line on $[0,14]$.", "Step 2: The integral equals the signed area: rectangle f...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-1876}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitu...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-1876}$.)
math-010678
Calculus: Derivatives — Power Rule
6
Use two approaches if possible: Let $f(x)=11x^2+(9)x$. (a) Compute $f'(20)$ using differentiation rules. (b) Compute $f'(20)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitl...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=11(a+h)^2+(9)(a+h)=11(a^2+2ah+h^2)+(9)a+(9)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{449}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=11,n=9,a=20$ both give 449.", "robustness_analysis": "Generality note: The rule-based m...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010679
Foundations of Calculus: Area vs Antiderivative
6
Explain what is being counted/optimized: Compute the definite integral $$\int_0^12 (-15x+(15))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signe...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-15}{2}x^2+(15)x$ since $F'(x)=-15x+(15)$.", "Step 2: By FTC, $\\int_0^12 (-15x+(15))dx = F(12)-F(0)$.", "Final step: $F(12)-F(...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-900}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitut...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-900}$.)
math-010680
Foundations of Calculus: Derivative Definition
6
Question: Let $f(x)=4x^2+(-14)x$. (a) Compute $f'(12)$ using differentiation rules. (b) Compute $f'(12)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling ...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(4)x+(-14)=8x+(-14)$.", "Step 2: Substitute $x=12$ to get $f'(12)=8(12)+(-14)=82$.", "Final step: Therefore \\boxed{82}." ], "final_answer"...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{82}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=4,n=-14,a=12$ both give 82.", "robustness_analysis": "Generality note: The rule-based method i...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010681
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Work this out carefully: Let $f(x)=5x^2+(26)x$. (a) Compute $f'(-19)$ using differentiation rules. (b) Compute $f'(-19)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly jus...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(5)x+(26)=10x+(26)$.", "Step 2: Substitute $x=-19$ to get $f'(-19)=10(-19)+(26)=-164$.", "Final step: Therefore \\boxed{-164}." ], "final_a...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-164}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=5,n=26,a=-19$ both give -164.", "robustness_analysis": "Sensitivity analysis: The rule...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-164}$.)
math-010682
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Compute the requested quantity: Let $f(x)=-12x^2+(-14)x$. (a) Compute $f'(12)$ using differentiation rules. (b) Compute $f'(12)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explic...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-12(a+h)^2+(-14)(a+h)=-12(a^2+2ah+h^2)+(-14)a+(-14)h$....
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-302}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-12,n=-14,a=12$ both give -302.", "robustness_analysis": "Ro...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010683
Calculus: Integrals — Exact Arithmetic
6
Give reasoning, not just computation: Compute the definite integral $$\int_0^39 (-12x+(26))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed a...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{-12}{2}x^2+(26)x$ since $F'(x)=-12x+(26)$.", "Step 2: By FTC, $\\int_0^39 (-12x+(26))dx = F(39)-F(0)$.", "Final step: $F(39)-F(...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-8112}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-12,q=26,t=39$ yields -8...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Remember: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010684
Calculus: Integrals — Fundamental Theorem of Calculus
6
Write the solution set clearly: Compute the definite integral $$\int_0^36 (9x+(-6))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' han...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{9}{2}x^2+(-6)x$ since $F'(x)=9x+(-6)$.", "Step 2: By FTC, $\\int_0^36 (9x+(-6))dx = F(36)-F(0)$.", "Final step: $F(36)-F(0)=\\f...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{5616}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=9,...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{5616}$.)
math-010685
Calculus: Integrals — Exact Arithmetic
6
Challenge: Compute the definite integral $$\int_0^33 (2x+(-31))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles the case when t...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{2}{2}x^2+(-31)x$ since $F'(x)=2x+(-31)$.", "Step 2: By FTC, $\\int_0^33 (2x+(-31))dx = F(33)-F(0)$.", "Final step: $F(33)-F(0)=...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{66}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=2,q=-31,t=33$ yields ...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010686
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Make each step logically reversible (or explain if not): Let $f(x)=1x^2+(-1)x$. (a) Compute $f'(-12)$ using differentiation rules. (b) Compute $f'(-12)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=1(a+h)^2+(-1)(a+h)=1(a^2+2ah+h^2)+(-1)a+(-1)h$.", ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-25}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=1,n=-1,a=-12$ both give -25.", "robustness_analysis": "If the problem were perturbed: The rul...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-25}$.)
math-010687
Calculus: Derivatives — Difference Quotient
6
Exercise: Let $f(x)=-1x^2+(17)x$. (a) Compute $f'(9)$ using differentiation rules. (b) Compute $f'(9)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling $h...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-1)x+(17)=-2x+(17)$.", "Step 2: Substitute $x=9$ to get $f'(9)=-2(9)+(17)=-1$.", "Final step: Therefore \\boxed{-1}." ], "final_answer": "...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-1}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-1,n=17,a=9$ both give -1.", "robustness_analysis": "Generalit...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-1}$.)
math-010688
Calculus: Integrals — Signed Area Interpretation
6
Solve with verification: Compute the definite integral $$\int_0^16 (12x+(25))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles t...
[ { "method_name": "Antiderivative (FTC)", "approach": "Find an antiderivative and evaluate $F(t)-F(0)$.", "steps": [ "Step 1: An antiderivative is $F(x)=\\frac{12}{2}x^2+(25)x$ since $F'(x)=12x+(25)$.", "Step 2: By FTC, $\\int_0^16 (12x+(25))dx = F(16)-F(0)$.", "Final step: $F(16)-F(0)=...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1936}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitut...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010689
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Solve with verification: Let $f(x)=4x^2+(-27)x$. (a) Compute $f'(-5)$ using differentiation rules. (b) Compute $f'(-5)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly just...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(4)x+(-27)=8x+(-27)$.", "Step 2: Substitute $x=-5$ to get $f'(-5)=8(-5)+(-27)=-67$.", "Final step: Therefore \\boxed{-67}." ], "final_answe...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-67}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=4,n=-27,a=-5$ both give -67.", "robustness_analysis": "Sensitivity ana...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Core principle: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-67}$.)
math-010690
Calculus: Derivatives — Difference Quotient
6
Warm-up: Let $f(x)=-2x^2+(4)x$. (a) Compute $f'(8)$ using differentiation rules. (b) Compute $f'(8)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling $h$ ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=-2(a+h)^2+(4)(a+h)=-2(a^2+2ah+h^2)+(4)a+(4)h$.", ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{-28}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-2,n=4,a=8$ both give -28.", "robustness_analysis": "If the problem were perturbed: The rule-...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010691
Calculus: Integrals — Linear Functions
6
Solve (and briefly cross-validate): Compute the definite integral $$\int_0^31 (-8x+(-24))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed are...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-8x+(-24)$ is a line on $[0,31]$.", "Step 2: The integral equals the signed area: rectangle fr...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{-4588}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitu...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Takeaway: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis.
math-010692
Calculus: Derivatives — Power Rule
6
Task: Let $f(x)=-3x^2+(-13)x$. (a) Compute $f'(20)$ using differentiation rules. (b) Compute $f'(20)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling $h$...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(-3)x+(-13)=-6x+(-13)$.", "Step 2: Substitute $x=20$ to get $f'(20)=-6(20)+(-13)=-133$.", "Final step: Therefore \\boxed{-133}." ], "final_...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-133}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=-3,n=-13,a=20$ both give -133.", "robustness_analysis": "Generality note: The rule-bas...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Key idea: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-133}$.)
math-010693
Calculus: Derivatives — Algebraic Expansion Pitfalls
6
Work carefully and justify each inference: Let $f(x)=10x^2+(-29)x$. (a) Compute $f'(-4)$ using differentiation rules. (b) Compute $f'(-4)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully ...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=10(a+h)^2+(-29)(a+h)=10(a^2+2ah+h^2)+(-29)a+(-29)h$.",...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-109}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=10,n=-29,a=-4$ both give -109.", "robustness_analysis": "Sensitivity ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-109}$.)
math-010694
Calculus: Integrals — Fundamental Theorem of Calculus
6
Give a theorem-based solution: Compute the definite integral $$\int_0^24 (14x+(-12))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' ha...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=14x+(-12)$ is a line on $[0,24]$.", "Step 2: The integral equals the signed area: rectangle fr...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{3744}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=14...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Takeaway: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{3744}$.)
math-010695
Calculus: Integrals — Fundamental Theorem of Calculus
6
Answer using clear logical steps: Compute the definite integral $$\int_0^11 (-2x+(-32))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area'...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-2x+(-32)$ is a line on $[0,11]$.", "Step 2: The integral equals the signed area: rectangle fr...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{-473}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituting $p=-2...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Takeaway: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{-473}$.)
math-010696
Calculus: Differentiation — Cross-Validation
6
Derive the result step-by-step: Let $f(x)=8x^2+(-7)x$. (a) Compute $f'(-14)$ using differentiation rules. (b) Compute $f'(-14)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explici...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=8(a+h)^2+(-7)(a+h)=8(a^2+2ah+h^2)+(-7)a+(-7)h$.", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{-231}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=8,n=-7,a=-14$ both give -231.", "robustness_analysis": "Robustness note: The rule-base...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{-231}$.)
math-010697
Calculus: Derivatives — Difference Quotient
6
Question: Let $f(x)=11x^2+(7)x$. (a) Compute $f'(5)$ using differentiation rules. (b) Compute $f'(5)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and explicitly justify cancelling $h$...
[ { "method_name": "Difference Quotient", "approach": "Use the definition of derivative and simplify the algebra until the limit is immediate.", "steps": [ "Step 1: Compute $\\frac{f(a+h)-f(a)}{h}$ for $h\\ne 0$.", "Step 2: Expand: $f(a+h)=11(a+h)^2+(7)(a+h)=11(a^2+2ah+h^2)+(7)a+(7)h$.", ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{117}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=11,n=7,a=5$ both give 117.", "robustness_analysis": "Robustness note: The rule-based method i...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Remember: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes. (Here the result is $\boxed{117}$.)
math-010698
Foundations of Calculus: Area vs Antiderivative
6
Give a theorem-based solution: Compute the definite integral $$\int_0^40 (13x+(-3))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' han...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=13x+(-3)$ is a line on $[0,40]$.", "Step 2: The integral equals the signed area: rectangle fro...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{10280}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substitu...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Key idea: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{10280}$.)
math-010699
Calculus: Derivatives — Power Rule
6
Explain what is being counted/optimized: Let $f(x)=2x^2+(7)x$. (a) Compute $f'(1)$ using differentiation rules. (b) Compute $f'(1)$ directly from the limit definition $f'(a)=\lim_{h\to 0}\frac{f(a+h)-f(a)}{h}$. (c) Explain why both computations must give the same number. In part (b), expand $(a+h)^2$ carefully and exp...
[ { "method_name": "Power Rule", "approach": "Differentiate term-by-term and evaluate at $x=a$.", "steps": [ "Step 1: Differentiate: $f'(x)=2(2)x+(7)=4x+(7)$.", "Step 2: Substitute $x=1$ to get $f'(1)=4(1)+(7)=11$.", "Final step: Therefore \\boxed{11}." ], "final_answer": "\\boxe...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{11}$.\nThe difference quotient simplifies to $2ma+n$, which matches evaluating the rule-based derivative $2mx+n$ at $x=a$. With $m=2,n=7,a=1$ both give 11.", "robustness_analysis": "Robustness ...
[ { "error_description": "Expanded $(a+h)^2$ as $a^2+h^2$ (missing $2ah$).", "why_plausible": "A common incorrect 'distribution' mistake.", "why_wrong": "The missing $2ah$ term changes the linear part and therefore the derivative.", "which_method_catches_it": "Power-rule method avoids this expansion e...
Takeaway: Derivatives computed by rules should match the limit definition because the rules are proved from that definition; using both is an excellent self-check against algebra mistakes.
math-010700
Calculus: Integrals — Linear Functions
6
Solve and sanity-check: Compute the definite integral $$\int_0^31 (-5x+(-13))\,dx.$$ (a) Compute using an antiderivative and the Fundamental Theorem of Calculus. (b) Compute by interpreting the integral as signed area under a line (decompose into a triangle + rectangle). (c) Explain briefly how 'signed area' handles t...
[ { "method_name": "Geometry (Triangle + Rectangle)", "approach": "Interpret the integral as signed area under a line segment and compute using basic area formulas.", "steps": [ "Step 1: The graph $y=-5x+(-13)$ is a line on $[0,31]$.", "Step 2: The integral equals the signed area: rectangle fr...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\frac{-5611}$.\nBoth methods compute the same quantity: the FTC gives $\\frac{p}2t^2+qt$, and the geometry method computes the same expression as triangle area plus rectangle area (with sign). Substituti...
[ { "error_description": "Integrated $px$ as $p\\ln x$ (confusing with $1/x$).", "why_plausible": "The log antiderivative is heavily memorized.", "why_wrong": "$\\int x\\,dx=\\frac{x^2}{2}$; $\\ln x$ corresponds to $1/x$, not $x$.", "which_method_catches_it": "Geometric method makes it clear the resul...
Core principle: Definite integrals can be computed analytically (FTC) or geometrically when the graph is simple; treating the integral as signed area keeps formulas valid even when the function dips below the axis. (Here the result is $\boxed{\frac{-5611}$.)