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math-016401
Real Analysis: Uniform Continuity (Variant C)
9
Warm-up: Let $f:(0,726)\to\mathbb{R}$ be $f(x)=\ln(43x)$. Is $f$ uniformly continuous on $(0,726)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{726}{n}$ and $y_n=\\frac{726}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\ln(...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016402
Real Analysis: Uniform Continuity (Variant B)
9
Solve and include a self-check: Let $f:(0,1252)\to\mathbb{R}$ be $f(x)=\frac{1}{(-14)x}$. Is $f$ uniformly continuous on $(0,1252)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Criterion", "approach": "To disprove uniform continuity, construct sequences with $|x_n-y_n|\\to 0$ but $|f(x_n)-f(y_n)|\\not\\to 0$.", "steps": [ "Step 1: Let $x_n=\\frac{1252}{n}$ and $y_n=\\frac{1252}{2n}$ in $(0,1252)$.", "Step 2: Then $|x_n-y_n|=\\frac{...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \\boxed{\\text{No}...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016403
Real Analysis: Uniform Continuity (Variant C)
9
Start by stating any domain restrictions: Let $f:(0,1476)\to\mathbb{R}$ be $f(x)=\frac{1}{(27)x}$. Is $f$ uniformly continuous on $(0,1476)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Criterion", "approach": "To disprove uniform continuity, construct sequences with $|x_n-y_n|\\to 0$ but $|f(x_n)-f(y_n)|\\not\\to 0$.", "steps": [ "Step 1: Let $x_n=\\frac{1476}{n}$ and $y_n=\\frac{1476}{2n}$ in $(0,1476)$.", "Step 2: Then $|x_n-y_n|=\\frac{...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016404
Real Analysis: Series — p-Series Threshold
9
Derive the result step-by-step: For the parameterized p-series below, determine whether it converges. Your solution must reference the threshold at $p=1$: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{55}{6}}}.$$ (a) Solve using...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{55}{6}$.", "Final step: By the p-series test, it conve...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{55}{6}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the problem ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Key idea: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{55}{6}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016405
Real Analysis: Uniform Continuity (Variant C)
9
Make each step logically reversible (or explain if not): Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(-12)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-uniform continuity.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016406
Real Analysis: Uniform Continuity (Variant A)
9
Answer with a short justification: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-12x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Characterization", "approach": "A function is uniformly continuous iff it sends Cauchy sequences to Cauchy sequences; use the global inequality $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: For all real $x,y$, $|\\sin x-\\sin y|\\le |x-y|$ (e.g., by MVT).",...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain.
math-016407
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Give reasoning, not just computation: Decide convergence/divergence of the series and justify with a named theorem: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{1}{11}}}.$$ (a) Solve using a named convergence test. (b) Give an ...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{1}{11}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test is a s...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{1}{11}$, so the series is divergent. (Here the result is $\boxed{\text{Diverges}$.)
math-016408
Real Analysis: Series — Parameter Sensitivity
9
Be explicit about assumptions: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{113}{36}}}.$$ (a) Solve using a named convergence test. (b) Give an indepen...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{113}{36}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity a...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{113}{36}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016409
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Keep the final answer in boxed form: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{113}{32}}}.$$ (a) Solve using a named convergence test. (b) Give an i...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{113}{32}$.", "Final step: By the p-series test, it con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{113}{32}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test is a ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{113}{32}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016410
Real Analysis: Uniform Continuity (Core)
9
Compute the requested quantity: Let $f:(0,54)\to\mathbb{R}$ be $f(x)=\frac{1}{(13)x}$. Is $f$ uniformly continuous on $(0,54)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Quantifier/Epsilon–Delta Contradiction", "approach": "Assume a global $\\delta(\\varepsilon)$ exists and show it fails near the singularity at 0.", "steps": [ "Step 1: Suppose $f$ is uniformly continuous and take $\\varepsilon=1$.", "Step 2: Let $\\delta>0$ be given by unif...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \\boxed{\\text{No}}.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016411
Real Analysis: Uniform Continuity (Variant A)
9
Solve (and briefly cross-validate): Let $f:(0,666)\to\mathbb{R}$ be $f(x)=\ln(35x)$. Is $f$ uniformly continuous on $(0,666)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{666}{n}$ and $y_n=\\frac{666}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\ln(...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robus...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016412
Real Analysis: Uniform Continuity (Variant B)
9
Explain each transformation: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(17)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-unifo...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016413
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Solve and then verify: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{85}{13}}}.$$ (a) Solve using...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{85}{13}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{85}{13}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the problem were per...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{85}{13}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016414
Real Analysis: Uniform Continuity (Variant B)
9
Write the solution set clearly: Let $f:(0,1097)\to\mathbb{R}$ be $f(x)=\frac{1}{(16)x}$. Is $f$ uniformly continuous on $(0,1097)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Criterion", "approach": "To disprove uniform continuity, construct sequences with $|x_n-y_n|\\to 0$ but $|f(x_n)-f(y_n)|\\not\\to 0$.", "steps": [ "Step 1: Let $x_n=\\frac{1097}{n}$ and $y_n=\\frac{1097}{2n}$ in $(0,1097)$.", "Step 2: Then $|x_n-y_n|=\\frac{...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \\boxed{\\text{No}}.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016415
Real Analysis: Uniform Continuity (Variant C)
9
Give a theorem-based solution: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(16x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Characterization", "approach": "A function is uniformly continuous iff it sends Cauchy sequences to Cauchy sequences; use the global inequality $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: For all real $x,y$, $|\\sin x-\\sin y|\\le |x-y|$ (e.g., by MVT).",...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Gen...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain.
math-016416
Real Analysis: Uniform Continuity (Variant A)
9
Answer using clear logical steps: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-1x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(-1)\\...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Sen...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016417
Real Analysis: Uniform Continuity (Variant C)
9
Where appropriate, name the theorem you use: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-10x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Characterization", "approach": "A function is uniformly continuous iff it sends Cauchy sequences to Cauchy sequences; use the global inequality $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: For all real $x,y$, $|\\sin x-\\sin y|\\le |x-y|$ (e.g., by MVT).",...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Sen...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016418
Real Analysis: Series — p-Series Threshold
9
Solve and justify each step: Is the following series convergent? Give one theorem-level reason and one alternative validation: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{47}{25}}}.$$ (a) Solve using a named convergence test. ...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{47}{25}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{47}{25}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Generality note: The p-series test is a ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{47}{25}$, so the series is convergent.
math-016419
Real Analysis: Series — Divergence at the Boundary Case
9
Solve and then verify: Is the following series convergent? Give one theorem-level reason and one alternative validation: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{106}{29}}}.$$ (a) Solve using a named convergence test. (b) G...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{106}{29}$.", "Final step: By the p-series test, it con...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{106}{29}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{106}{29}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016420
Real Analysis: Series — p-Series Threshold
9
Determine the requested value: Decide convergence/divergence of the series and justify with a named theorem: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{55}{14}}}.$$ (a) Solve using a named convergence test. (b) Give an indepe...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{55}{14}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the problem were perturbed: The p-series te...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{55}{14}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016421
Real Analysis: Uniform Continuity (Variant B)
9
Track units/moduli carefully: Let $f:(0,221)\to\mathbb{R}$ be $f(x)=\ln(4x)$. Is $f$ uniformly continuous on $(0,221)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Epsilon–Delta with Scale Trick", "approach": "Assume uniform continuity; choose $\\varepsilon<|\\ln 2|$ and show $x$ and $2x$ violate it for sufficiently small $x$.", "steps": [ "Step 1: Assume uniform continuity holds and choose $\\varepsilon=|\\ln 2|/2$.", "Step 2: Let $\...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016422
Real Analysis: Series — Divergence at the Boundary Case
9
Problem: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{102}{35}}}.$$ (a) Solve using a named conv...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{102}{35}$.", "Final step: By the p-series test, it con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{102}{35}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the proble...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{102}{35}$, so the series is convergent.
math-016423
Real Analysis: Series — p-Series Threshold
9
Write the solution set clearly: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{68}{33}}}.$$ (a) Solve using a named convergence test. (b) Give an indepen...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{68}{33}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{68}{33}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test is a s...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{68}{33}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016424
Real Analysis: Uniform Continuity (Core)
9
Solve with verification: Let $f:(0,1674)\to\mathbb{R}$ be $f(x)=\frac{1}{(3)x}$. Is $f$ uniformly continuous on $(0,1674)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Quantifier/Epsilon–Delta Contradiction", "approach": "Assume a global $\\delta(\\varepsilon)$ exists and show it fails near the singularity at 0.", "steps": [ "Step 1: Suppose $f$ is uniformly continuous and take $\\varepsilon=1$.", "Step 2: Let $\\delta>0$ be given by unif...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \\boxed{\\text{No}}.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016425
Real Analysis: Series — Integral Test for Power Laws
9
Do not skip justification steps: Decide convergence/divergence of the series and justify with a named theorem: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{7}{12}}}.$$ (a) Solve using a named convergence test. (b) Give an indep...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{7}{12}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Generality note: The p-series test is a ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{7}{12}$, so the series is divergent.
math-016426
Real Analysis: Uniform Continuity (Core)
9
Warm-up: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-28x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Characterization", "approach": "A function is uniformly continuous iff it sends Cauchy sequences to Cauchy sequences; use the global inequality $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: For all real $x,y$, $|\\sin x-\\sin y|\\le |x-y|$ (e.g., by MVT).",...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Gen...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016427
Real Analysis: Uniform Continuity (Variant B)
9
Give a fully justified solution: Let $f:(0,1619)\to\mathbb{R}$ be $f(x)=\ln(10x)$. Is $f$ uniformly continuous on $(0,1619)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{1619}{n}$ and $y_n=\\frac{1619}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\l...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": "Gener...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016428
Real Analysis: Uniform Continuity (Core)
9
Find the exact value: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(27x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(27)\\...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain.
math-016429
Real Analysis: Uniform Continuity (Variant A)
9
Indicate where a theorem is used: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(-13)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Explicit Sequence Counterexample", "approach": "Pick sequences approaching each other at infinity but whose squares stay separated.", "steps": [ "Step 1: Let $x_n=n$ and $y_n=n+\\frac{1}{n}$.", "Step 2: Then $|x_n-y_n|=\\frac{1}{n}\\to 0$.", "Final step: But $|f(x_n)-...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-uniform continuity.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016430
Real Analysis: Uniform Continuity (Variant B)
9
Start by stating any domain restrictions: Let $f:(0,1431)\to\mathbb{R}$ be $f(x)=\frac{1}{(19)x}$. Is $f$ uniformly continuous on $(0,1431)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Criterion", "approach": "To disprove uniform continuity, construct sequences with $|x_n-y_n|\\to 0$ but $|f(x_n)-f(y_n)|\\not\\to 0$.", "steps": [ "Step 1: Let $x_n=\\frac{1431}{n}$ and $y_n=\\frac{1431}{2n}$ in $(0,1431)$.", "Step 2: Then $|x_n-y_n|=\\frac{...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \\boxed{\\text{No}}.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016431
Real Analysis: Uniform Continuity (Variant C)
9
Give a theorem-based solution: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(26)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Explicit Sequence Counterexample", "approach": "Pick sequences approaching each other at infinity but whose squares stay separated.", "steps": [ "Step 1: Let $x_n=n$ and $y_n=n+\\frac{1}{n}$.", "Step 2: Then $|x_n-y_n|=\\frac{1}{n}\\to 0$.", "Final step: But $|f(x_n)-...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-unifo...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016432
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Answer with a short justification: Decide convergence/divergence of the series and justify with a named theorem: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{65}{31}}}.$$ (a) Solve using a named convergence test. (b) Give an in...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{65}{31}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{65}{31}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016433
Real Analysis: Series — Divergence at the Boundary Case
9
Work carefully and justify each inference: Is the following series convergent? Give one theorem-level reason and one alternative validation: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{108}{35}}}.$$ (a) Solve using a named con...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{108}{35}$.", "Final step: By the p-series test, it con...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{108}{35}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness note: The p-series test is a...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Key idea: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{108}{35}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016434
Real Analysis: Uniform Continuity (Core)
9
Answer with a short justification: Let $f:(0,1580)\to\mathbb{R}$ be $f(x)=\frac{1}{(5)x}$. Is $f$ uniformly continuous on $(0,1580)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Quantifier/Epsilon–Delta Contradiction", "approach": "Assume a global $\\delta(\\varepsilon)$ exists and show it fails near the singularity at 0.", "steps": [ "Step 1: Suppose $f$ is uniformly continuous and take $\\varepsilon=1$.", "Step 2: Let $\\delta>0$ be given by unif...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both c...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016435
Real Analysis: Uniform Continuity (Core)
9
Try to avoid pattern-matching; explain why: Let $f:(0,1598)\to\mathbb{R}$ be $f(x)=\frac{1}{(13)x}$. Is $f$ uniformly continuous on $(0,1598)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Quantifier/Epsilon–Delta Contradiction", "approach": "Assume a global $\\delta(\\varepsilon)$ exists and show it fails near the singularity at 0.", "steps": [ "Step 1: Suppose $f$ is uniformly continuous and take $\\varepsilon=1$.", "Step 2: Let $\\delta>0$ be given by unif...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \\boxed{\\text{No}...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016436
Real Analysis: Uniform Continuity (Variant A)
9
Challenge: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-22x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(-22)\...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustnes...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016437
Real Analysis: Uniform Continuity (Variant B)
9
State any required conditions first: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(15)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Explicit Sequence Counterexample", "approach": "Pick sequences approaching each other at infinity but whose squares stay separated.", "steps": [ "Step 1: Let $x_n=n$ and $y_n=n+\\frac{1}{n}$.", "Step 2: Then $|x_n-y_n|=\\frac{1}{n}\\to 0$.", "Final step: But $|f(x_n)-...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016438
Real Analysis: Uniform Continuity (Variant A)
9
Explain why your operations are valid: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(2x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(2)\\c...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "If ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016439
Real Analysis: Uniform Continuity (Core)
9
Proceed methodically: Let $f:(0,1476)\to\mathbb{R}$ be $f(x)=\frac{1}{(19)x}$. Is $f$ uniformly continuous on $(0,1476)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Criterion", "approach": "To disprove uniform continuity, construct sequences with $|x_n-y_n|\\to 0$ but $|f(x_n)-f(y_n)|\\not\\to 0$.", "steps": [ "Step 1: Let $x_n=\\frac{1476}{n}$ and $y_n=\\frac{1476}{2n}$ in $(0,1476)$.", "Step 2: Then $|x_n-y_n|=\\frac{...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016440
Real Analysis: Uniform Continuity (Variant B)
9
Task: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(-1)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-unifo...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016441
Real Analysis: Series — Integral Test for Power Laws
9
Compute the requested quantity: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{89}{20}}}.$$ (a) So...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{89}{20}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{89}{20}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Generality note: The p-series test is a ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{89}{20}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016442
Real Analysis: Series — Parameter Sensitivity
9
Determine the requested value: Is the following series convergent? Give one theorem-level reason and one alternative validation: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{43}{8}}}.$$ (a) Solve using a named convergence test....
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{43}{8}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test is a sp...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{43}{8}$, so the series is convergent.
math-016443
Real Analysis: Uniform Continuity (Variant C)
9
Show all reasoning: Let $f:(0,1399)\to\mathbb{R}$ be $f(x)=\frac{1}{(28)x}$. Is $f$ uniformly continuous on $(0,1399)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Criterion", "approach": "To disprove uniform continuity, construct sequences with $|x_n-y_n|\\to 0$ but $|f(x_n)-f(y_n)|\\not\\to 0$.", "steps": [ "Step 1: Let $x_n=\\frac{1399}{n}$ and $y_n=\\frac{1399}{2n}$ in $(0,1399)$.", "Step 2: Then $|x_n-y_n|=\\frac{...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \\boxed{\\text{No}...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016444
Real Analysis: Uniform Continuity (Variant C)
9
Work carefully and justify each inference: Let $f:(0,268)\to\mathbb{R}$ be $f(x)=\ln(44x)$. Is $f$ uniformly continuous on $(0,268)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{268}{n}$ and $y_n=\\frac{268}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\ln(...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016445
Real Analysis: Uniform Continuity (Variant B)
9
Explain each transformation: Let $f:(0,568)\to\mathbb{R}$ be $f(x)=\frac{1}{(-22)x}$. Is $f$ uniformly continuous on $(0,568)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Quantifier/Epsilon–Delta Contradiction", "approach": "Assume a global $\\delta(\\varepsilon)$ exists and show it fails near the singularity at 0.", "steps": [ "Step 1: Suppose $f$ is uniformly continuous and take $\\varepsilon=1$.", "Step 2: Let $\\delta>0$ be given by unif...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both conclude \...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016446
Real Analysis: Series — Divergence at the Boundary Case
9
Be explicit about assumptions: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{41}{12}}}.$$ (a) Solve using a named convergence test. (b) Give an independ...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{41}{12}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{41}{12}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity an...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{41}{12}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016447
Real Analysis: Uniform Continuity (Variant A)
9
Provide a rigorous solution: Let $f:(0,225)\to\mathbb{R}$ be $f(x)=\frac{1}{(24)x}$. Is $f$ uniformly continuous on $(0,225)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Quantifier/Epsilon–Delta Contradiction", "approach": "Assume a global $\\delta(\\varepsilon)$ exists and show it fails near the singularity at 0.", "steps": [ "Step 1: Suppose $f$ is uniformly continuous and take $\\varepsilon=1$.", "Step 2: Let $\\delta>0$ be given by unif...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both c...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016448
Real Analysis: Uniform Continuity (Variant C)
9
Answer using clear logical steps: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(18)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Explicit Sequence Counterexample", "approach": "Pick sequences approaching each other at infinity but whose squares stay separated.", "steps": [ "Step 1: Let $x_n=n$ and $y_n=n+\\frac{1}{n}$.", "Step 2: Then $|x_n-y_n|=\\frac{1}{n}\\to 0$.", "Final step: But $|f(x_n)-...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-unifo...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016449
Real Analysis: Uniform Continuity (Variant C)
9
Checkpoint: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(11)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Explicit Sequence Counterexample", "approach": "Pick sequences approaching each other at infinity but whose squares stay separated.", "steps": [ "Step 1: Let $x_n=n$ and $y_n=n+\\frac{1}{n}$.", "Step 2: Then $|x_n-y_n|=\\frac{1}{n}\\to 0$.", "Final step: But $|f(x_n)-...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016450
Real Analysis: Series — Integral Test for Power Laws
9
Challenge: Decide convergence/divergence of the series and justify with a named theorem: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{34}{7}}}.$$ (a) Solve using a named convergence test. (b) Give an independent cross-check usi...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{34}{7}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness note: The p-s...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{34}{7}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016451
Real Analysis: Uniform Continuity (Variant B)
9
Explain why your operations are valid: Let $f:(0,1617)\to\mathbb{R}$ be $f(x)=\frac{1}{(-22)x}$. Is $f$ uniformly continuous on $(0,1617)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Criterion", "approach": "To disprove uniform continuity, construct sequences with $|x_n-y_n|\\to 0$ but $|f(x_n)-f(y_n)|\\not\\to 0$.", "steps": [ "Step 1: Let $x_n=\\frac{1617}{n}$ and $y_n=\\frac{1617}{2n}$ in $(0,1617)$.", "Step 2: Then $|x_n-y_n|=\\frac{...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both c...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016452
Real Analysis: Uniform Continuity (Variant C)
9
Answer using clear logical steps: Let $f:(0,1627)\to\mathbb{R}$ be $f(x)=\frac{1}{(30)x}$. Is $f$ uniformly continuous on $(0,1627)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Quantifier/Epsilon–Delta Contradiction", "approach": "Assume a global $\\delta(\\varepsilon)$ exists and show it fails near the singularity at 0.", "steps": [ "Step 1: Suppose $f$ is uniformly continuous and take $\\varepsilon=1$.", "Step 2: Let $\\delta>0$ be given by unif...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nBoth methods exploit the same obstruction: arbitrarily close inputs near 0 can have arbitrarily far apart outputs for $1/x$, so no single global modulus of continuity exists. Both c...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016453
Real Analysis: Uniform Continuity (Variant C)
9
Write the solution set clearly: Let $f:(0,35)\to\mathbb{R}$ be $f(x)=\ln(25x)$. Is $f$ uniformly continuous on $(0,35)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Epsilon–Delta with Scale Trick", "approach": "Assume uniform continuity; choose $\\varepsilon<|\\ln 2|$ and show $x$ and $2x$ violate it for sufficiently small $x$.", "steps": [ "Step 1: Assume uniform continuity holds and choose $\\varepsilon=|\\ln 2|/2$.", "Step 2: Let $\...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016454
Real Analysis: Uniform Continuity (Variant B)
9
Checkpoint: Let $f:(0,1550)\to\mathbb{R}$ be $f(x)=\ln(4x)$. Is $f$ uniformly continuous on $(0,1550)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{1550}{n}$ and $y_n=\\frac{1550}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\l...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.",...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016455
Real Analysis: Series — Integral Test for Power Laws
9
Start by stating any domain restrictions: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{9}{11}}}.$...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{9}{11}$.", "Final step: By the p-series test, it diver...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{9}{11}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Robustness note: The p-series test is a specia...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{9}{11}$, so the series is divergent.
math-016456
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Write the solution set clearly: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{47}{5}}}.$$ (a) Solve using a named convergence test. (b) Give an independ...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{47}{5}$.", "Final step: By the p-series test, it conve...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{47}{5}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness note: The p-series test is a special...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{47}{5}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016457
Real Analysis: Series — Parameter Sensitivity
9
Keep the final answer in boxed form: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{43}{39}}}.$$ (a) Solve using a named convergence test. (b) Give an in...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{43}{39}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{43}{39}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: T...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Key idea: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{43}{39}$, so the series is convergent.
math-016458
Real Analysis: Series — Integral Test for Power Laws
9
Question: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{35}{13}}}.$$ (a) Solve using a named conv...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{35}{13}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{35}{13}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Generality note: The p-series test is a specia...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Key idea: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{35}{13}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016459
Real Analysis: Uniform Continuity (Variant B)
9
Prompt: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-27x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(-27)\...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Robustnes...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016460
Real Analysis: Series — p-Series Threshold
9
Explain why your operations are valid: Decide convergence/divergence of the series and justify with a named theorem: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{65}{34}}}.$$ (a) Solve using a named convergence test. (b) Give a...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{65}{34}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness note: The p-series test is a ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{65}{34}$, so the series is convergent.
math-016461
Real Analysis: Uniform Continuity (Core)
9
Prompt: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(13)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Explicit Sequence Counterexample", "approach": "Pick sequences approaching each other at infinity but whose squares stay separated.", "steps": [ "Step 1: Let $x_n=n$ and $y_n=n+\\frac{1}{n}$.", "Step 2: Then $|x_n-y_n|=\\frac{1}{n}\\to 0$.", "Final step: But $|f(x_n)-...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-uniform continuity.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016462
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Compute the requested quantity: For the parameterized p-series below, determine whether it converges. Your solution must reference the threshold at $p=1$: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{23}{11}}}.$$ (a) Solve usin...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{23}{11}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness note: The p-series test is a ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{23}{11}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016463
Real Analysis: Series — Necessary vs Sufficient Conditions
9
State any required conditions first: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{24}{5}}}.$$ (a...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{24}{5}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness note...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{24}{5}$, so the series is convergent.
math-016464
Real Analysis: Series — Integral Test for Power Laws
9
Work this out carefully: For the parameterized p-series below, determine whether it converges. Your solution must reference the threshold at $p=1$: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{7}{29}}}.$$ (a) Solve using a name...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{7}{29}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Generality note: The p-series test is a specia...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{7}{29}$, so the series is divergent.
math-016465
Real Analysis: Series — p-Series Threshold
9
Provide a rigorous solution: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{9}{22}}}.$$ (a) Solve ...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{9}{22}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Generality note: The p-series test is a specia...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{9}{22}$, so the series is divergent. (Here the result is $\boxed{\text{Diverges}$.)
math-016466
Real Analysis: Series — Divergence at the Boundary Case
9
Solve with verification: Decide convergence/divergence of the series and justify with a named theorem: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{114}{31}}}.$$ (a) Solve using a named convergence test. (b) Give an independent...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{114}{31}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{114}{31}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016467
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Proceed methodically: Is the following series convergent? Give one theorem-level reason and one alternative validation: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{57}{17}}}.$$ (a) Solve using a named convergence test. (b) Giv...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{57}{17}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the problem...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{57}{17}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016468
Real Analysis: Series — Divergence at the Boundary Case
9
State any required conditions first: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{99}{20}}}.$$ (a) Solve using a named convergence test. (b) Give an in...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{99}{20}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the problem...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{99}{20}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016469
Real Analysis: Series — p-Series Threshold
9
Give a theorem-based solution: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{14}{15}}}.$$ (a) Sol...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{14}{15}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Generality note: The p-series test is a speci...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Remember: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{14}{15}$, so the series is divergent.
math-016470
Real Analysis: Uniform Continuity (Variant B)
9
Give a theorem-based solution: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(-28)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-uniform continuity.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016471
Real Analysis: Uniform Continuity (Variant C)
9
Give an answer and a quick verification: Let $f:(0,787)\to\mathbb{R}$ be $f(x)=\ln(54x)$. Is $f$ uniformly continuous on $(0,787)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{787}{n}$ and $y_n=\\frac{787}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\ln(...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016472
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Prompt: Is the following series convergent? Give one theorem-level reason and one alternative validation: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{31}{10}}}.$$ (a) Solve using a named convergence test. (b) Give an independe...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{31}{10}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness not...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{31}{10}$, so the series is convergent.
math-016473
Real Analysis: Uniform Continuity (Variant A)
9
Try to avoid pattern-matching; explain why: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-7x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(-7)\\...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Sensitivi...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain.
math-016474
Real Analysis: Uniform Continuity (Variant C)
9
Task: Let $f:(0,1661)\to\mathbb{R}$ be $f(x)=\ln(45x)$. Is $f$ uniformly continuous on $(0,1661)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{1661}{n}$ and $y_n=\\frac{1661}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\l...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016475
Real Analysis: Uniform Continuity (Core)
9
Keep the final answer in boxed form: Let $f:(0,1947)\to\mathbb{R}$ be $f(x)=\ln(17x)$. Is $f$ uniformly continuous on $(0,1947)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Epsilon–Delta with Scale Trick", "approach": "Assume uniform continuity; choose $\\varepsilon<|\\ln 2|$ and show $x$ and $2x$ violate it for sufficiently small $x$.", "steps": [ "Step 1: Assume uniform continuity holds and choose $\\varepsilon=|\\ln 2|/2$.", "Step 2: Let $\...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.",...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016476
Real Analysis: Uniform Continuity (Variant A)
9
Compute the requested quantity: Let $f:(0,1224)\to\mathbb{R}$ be $f(x)=\ln(23x)$. Is $f$ uniformly continuous on $(0,1224)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Epsilon–Delta with Scale Trick", "approach": "Assume uniform continuity; choose $\\varepsilon<|\\ln 2|$ and show $x$ and $2x$ violate it for sufficiently small $x$.", "steps": [ "Step 1: Assume uniform continuity holds and choose $\\varepsilon=|\\ln 2|/2$.", "Step 2: Let $\...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robus...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016477
Real Analysis: Uniform Continuity (Variant C)
9
Task: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-5x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(-5)\\...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Sensitivi...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016478
Real Analysis: Series — Divergence at the Boundary Case
9
Find the exact value: For the parameterized p-series below, determine whether it converges. Your solution must reference the threshold at $p=1$: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{38}{13}}}.$$ (a) Solve using a named ...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{38}{13}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{38}{13}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the problem were per...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{38}{13}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016479
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Explain why your operations are valid: Classify the infinite series (convergent or divergent). Provide two independent arguments (e.g., p-series test and integral test): Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{11}{20}}}.$$ ...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{11}{20}$.", "Final step: By the p-series test, it dive...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{11}{20}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Robustness no...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{11}{20}$, so the series is divergent. (Here the result is $\boxed{\text{Diverges}$.)
math-016480
Real Analysis: Uniform Continuity (Variant A)
9
Give a theorem-based solution: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-25x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(-25)\...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Rob...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain.
math-016481
Real Analysis: Uniform Continuity (Variant B)
9
Prompt: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(1x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Characterization", "approach": "A function is uniformly continuous iff it sends Cauchy sequences to Cauchy sequences; use the global inequality $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: For all real $x,y$, $|\\sin x-\\sin y|\\le |x-y|$ (e.g., by MVT).",...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "Robustnes...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)
math-016482
Real Analysis: Uniform Continuity (Variant B)
9
Exercise: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(15x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Cauchy-Sequence Characterization", "approach": "A function is uniformly continuous iff it sends Cauchy sequences to Cauchy sequences; use the global inequality $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: For all real $x,y$, $|\\sin x-\\sin y|\\le |x-y|$ (e.g., by MVT).",...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "If ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain.
math-016483
Real Analysis: Uniform Continuity (Variant C)
9
Challenge: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(1)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-uniform continuity.", "rob...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016484
Real Analysis: Uniform Continuity (Core)
9
Write the solution set clearly: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(-7)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Explicit Sequence Counterexample", "approach": "Pick sequences approaching each other at infinity but whose squares stay separated.", "steps": [ "Step 1: Let $x_n=n$ and $y_n=n+\\frac{1}{n}$.", "Step 2: Then $|x_n-y_n|=\\frac{1}{n}\\to 0$.", "Final step: But $|f(x_n)-...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain.
math-016485
Real Analysis: Uniform Continuity (Core)
9
Explain why your operations are valid: Let $f:(0,1765)\to\mathbb{R}$ be $f(x)=\ln(25x)$. Is $f$ uniformly continuous on $(0,1765)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{1765}{n}$ and $y_n=\\frac{1765}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\l...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robus...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016486
Real Analysis: Series — Integral Test for Power Laws
9
Solve and include a self-check: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{99}{14}}}.$$ (a) Solve using a named convergence test. (b) Give an indepen...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{99}{14}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{99}{14}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Robustness note: The p-...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{99}{14}$, so the series is convergent.
math-016487
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Solve and then verify: For the parameterized p-series below, determine whether it converges. Your solution must reference the threshold at $p=1$: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{86}{33}}}.$$ (a) Solve using a named...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{86}{33}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{86}{33}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "If the problem were perturbed: The p-ser...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{86}{33}$, so the series is convergent.
math-016488
Real Analysis: Series — Divergence at the Boundary Case
9
Track units/moduli carefully: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{74}{19}}}.$$ (a) Solve using a named convergence test. (b) Give an independe...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{74}{19}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{74}{19}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test ...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{74}{19}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016489
Real Analysis: Series — Divergence at the Boundary Case
9
Solve (and briefly cross-validate): Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{44}{21}}}.$$ (a) Solve using a named convergence test. (b) Give an ind...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{44}{21}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{44}{21}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Generality note: The p-...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{44}{21}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016490
Real Analysis: Series — p-Series Threshold
9
Solve and include a self-check: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{74}{33}}}.$$ (a) Solve using a named convergence test. (b) Give an indepen...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{74}{33}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test is a s...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{74}{33}$, so the series is convergent.
math-016491
Real Analysis: Uniform Continuity (Variant B)
9
Provide a rigorous solution: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(10)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016492
Real Analysis: Series — Integral Test for Power Laws
9
Give an answer and a quick verification: For the parameterized p-series below, determine whether it converges. Your solution must reference the threshold at $p=1$: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{4}{25}}}.$$ (a) So...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Diverges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{4}{25}$ is \\le 1, so both methods agree on \\boxed{\\text{Diverges}}.", "robustness_analysis": "Generality not...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Takeaway: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{4}{25}$, so the series is divergent. (Here the result is $\boxed{\text{Diverges}$.)
math-016493
Real Analysis: Uniform Continuity (Core)
9
Solve (and briefly cross-validate): Let $f:(0,1706)\to\mathbb{R}$ be $f(x)=\ln(7x)$. Is $f$ uniformly continuous on $(0,1706)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Epsilon–Delta with Scale Trick", "approach": "Assume uniform continuity; choose $\\varepsilon<|\\ln 2|$ and show $x$ and $2x$ violate it for sufficiently small $x$.", "steps": [ "Step 1: Assume uniform continuity holds and choose $\\varepsilon=|\\ln 2|/2$.", "Step 2: Let $\...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robus...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Takeaway: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016494
Real Analysis: Uniform Continuity (Variant C)
9
Give a theorem-based solution: Let $f:(0,1087)\to\mathbb{R}$ be $f(x)=\ln(8x)$. Is $f$ uniformly continuous on $(0,1087)$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Close Inputs, Fixed Output Gap", "approach": "Use a sequence approaching 0 where scaling by 2 produces a constant log-gap.", "steps": [ "Step 1: Let $x_n=\\frac{1087}{n}$ and $y_n=\\frac{1087}{2n}$.", "Step 2: Then $|x_n-y_n|=\\frac{A}{2n}\\to 0$.", "Step 3: But $|\\l...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{No}$.\nBoth arguments exhibit a uniform obstruction near 0: inputs with ratio 2 can be arbitrarily close, while the log difference stays $\\ln 2$. Thus both conclude \\boxed{\\text{No}}.", "robustness_analysis": "If th...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016495
Real Analysis: Uniform Continuity (Variant C)
9
Complete the analysis: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(-11)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-uniform continuity.", ...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Remember: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016496
Real Analysis: Series — Necessary vs Sufficient Conditions
9
Give an answer and a quick verification: Is the following series convergent? Give one theorem-level reason and one alternative validation: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{35}{8}}}.$$ (a) Solve using a named converg...
[ { "method_name": "Integral Test", "approach": "Apply the integral test to $f(x)=x^{-p}$ and analyze $\\int_1^\\infty x^{-p}\\,dx$.", "steps": [ "Step 1: Let $f(x)=x^{-p}$ for $x\\ge 1$. For $p>0$, $f$ is positive and decreasing.", "Step 2: By the integral test, $\\sum_{n=1}^\\infty f(n)$ con...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{35}{8}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity ana...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{35}{8}$, so the series is convergent.
math-016497
Real Analysis: Uniform Continuity (Variant B)
9
Track quantifiers carefully: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=(-14)x^2$ with $c\ne 0$. Is $f$ uniformly continuous on $\mathbb{R}$? Give a proof. Include a brief verification/cross-check at the end.
[ { "method_name": "Mean Value Theorem Blow-Up", "approach": "Use MVT to show that on unbounded domains, the derivative growth makes a uniform modulus impossible.", "steps": [ "Step 1: Suppose uniform continuity holds. Take $\\varepsilon=1$ and let $\\delta>0$ correspond.", "Step 2: Choose $x$...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{\\text{No}$.\nThe sequence method explicitly exhibits $|x_n-y_n|\\to 0$ while $|f(x_n)-f(y_n)|\\not\\to 0$. The MVT method formalizes the same idea via unbounded derivative growth. Both conclude non-unifo...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Key idea: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is No for the stated domain. (Here the result is $\boxed{\text{No}$.)
math-016498
Real Analysis: Series — Divergence at the Boundary Case
9
Write the solution set clearly: For the parameterized p-series below, determine whether it converges. Your solution must reference the threshold at $p=1$: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{73}{33}}}.$$ (a) Solve usin...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{73}{33}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{73}{33}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity an...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Key idea: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{73}{33}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016499
Real Analysis: Series — Integral Test for Power Laws
9
Warm-up: Analyze the series using two distinct convergence tests and reconcile them: Decide whether the series converges or diverges. You must justify your answer by naming a theorem. $$\sum_{n=1}^\infty \frac{1}{n^{\frac{83}{12}}}.$$ (a) Solve using a named convergence test. (b) Give an independent cross-check using ...
[ { "method_name": "p-Series Test", "approach": "Use the theorem that $\\sum 1/n^p$ converges iff $p>1$.", "steps": [ "Step 1: Recognize the given series as a p-series $\\sum_{n=1}^\\infty 1/n^p$ with $p>0$.", "Step 2: Here $p=\\frac{83}{12}$.", "Final step: By the p-series test, it conv...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Converges}$.\nBoth tests reduce to the same threshold $p=1$. Here $p=\\frac{83}{12}$ is > 1, so both methods agree on \\boxed{\\text{Converges}}.", "robustness_analysis": "Sensitivity analysis: The p-series test is a s...
[ { "error_description": "Concluded convergence because $1/n^p\\to 0$.", "why_plausible": "The term test (terms go to 0) is often overused as if it were sufficient.", "why_wrong": "While $a_n\\to 0$ is necessary, it is not sufficient (e.g., $\\sum 1/n$ diverges).", "which_method_catches_it": "Integral...
Core principle: For the p-series $\sum 1/n^p$, convergence is controlled entirely by whether $p>1$. Here $p=\frac{83}{12}$, so the series is convergent. (Here the result is $\boxed{\text{Converges}$.)
math-016500
Real Analysis: Uniform Continuity (Core)
9
Give an answer and a quick verification: Let $f:\mathbb{R}\to\mathbb{R}$ be $f(x)=\sin(-3x)$. Prove that $f$ is uniformly continuous on $\mathbb{R}$. Include a brief verification/cross-check at the end.
[ { "method_name": "Lipschitz via Mean Value Theorem", "approach": "Use MVT to get a global Lipschitz bound $|\\sin x-\\sin y|\\le |x-y|$.", "steps": [ "Step 1: Apply MVT to $g(t)=\\sin(ct)$: there exists $\\xi$ between $x$ and $y$ with $g(x)-g(y)=g'(\\xi)(x-y)$.", "Step 2: Since $g'(t)=(-3)\\...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{\\text{Yes}$.\nThe MVT proof gives an explicit global Lipschitz modulus, which immediately implies the Cauchy-sequence property. Both are equivalent characterizations of uniform continuity.", "robustness_analysis": "If the pr...
[ { "error_description": "Assumed continuity implies uniform continuity without checking compactness or a global bound.", "why_plausible": "Heine–Cantor is often remembered without its hypotheses.", "why_wrong": "Continuity implies uniform continuity only on compact sets; on non-compact domains there are ...
Core principle: Uniform continuity is global and depends on the domain: compactness/Lipschitz bounds guarantee it, while singularities or unbounded derivative growth often destroy it. Here the answer is Yes for the stated domain. (Here the result is $\boxed{\text{Yes}$.)