answer
string
choices
dict
id
string
kind
string
lang
string
question
string
steps
list
subject
string
text
string
topic
string
Determinant: 238.
null
mat_0651
worked_example
en
Compute det [[15,1],[2,16]] step by step.
[ "ad − bc.", "15×16 − 1×2.", "= 238." ]
math
Answer: Determinant: 238. Steps: 1. ad − bc. 2. 15×16 − 1×2. 3. = 238.
linear_algebra
It averages one variable given another's value, the basis of regression prediction.
null
mat_0652
concept
en
What is conditional expectation?
[ "It averages one variable given another's value, the basis of regression prediction.", "So the answer stands: It averages one variable given another's value, the basis of regression prediction." ]
math
Answer: It averages one variable given another's value, the basis of regression prediction. Steps: 1. It averages one variable given another's value, the basis of regression prediction. 2. So the answer stands: It averages one variable given another's value, the basis of regression prediction.
probability
lcm = 120.
null
mat_0653
worked_example
en
Compute lcm(15, 8) step by step.
[ "gcd(15,8) = 1.", "15×8/1.", "= 120." ]
math
Answer: lcm = 120. Steps: 1. gcd(15,8) = 1. 2. 15×8/1. 3. = 120.
number_theory
They arrange balanced experiments, with each pair meeting exactly lambda times.
null
mat_0654
concept
en
Why block designs?
[ "They arrange balanced experiments, with each pair meeting exactly lambda times.", "So the answer stands: They arrange balanced experiments, with each pair meeting exactly lambda times." ]
math
Answer: They arrange balanced experiments, with each pair meeting exactly lambda times. Steps: 1. They arrange balanced experiments, with each pair meeting exactly lambda times. 2. So the answer stands: They arrange balanced experiments, with each pair meeting exactly lambda times.
combinatorics
The sum is 66.
{ "A": "55", "B": "77", "C": "88", "D": "66" }
mat_0655
multiple_choice
en
What is the sum 1 + 2 + ... + 11?
[ "11×12/2.", "Sum = 66.", "Select option D." ]
math
Answer: 66 Steps: 1. 11×12/2. 2. Sum = 66. 3. Select option D. Answer: (D)
proofs
Convergence decides whether infinite processes settle, separating meaningful sums from nonsense.
null
mat_0656
concept
en
Why study convergence?
[ "Convergence decides whether infinite processes settle, separating meaningful sums from nonsense.", "So the answer stands: Convergence decides whether infinite processes settle, separating meaningful sums from nonsense." ]
math
Answer: Convergence decides whether infinite processes settle, separating meaningful sums from nonsense. Steps: 1. Convergence decides whether infinite processes settle, separating meaningful sums from nonsense. 2. So the answer stands: Convergence decides whether infinite processes settle, separating meaningful sums f...
calculus
Trace: 33.
null
mat_0657
worked_example
en
Compute the trace of [[16,0],[0,17]].
[ "Sum diagonal.", "16 + 17.", "= 33." ]
math
Answer: Trace: 33. Steps: 1. Sum diagonal. 2. 16 + 17. 3. = 33.
linear_algebra
E = 8.5.
null
mat_0658
worked_example
en
Compute E of a uniform draw from {1..16}.
[ "Mean of 1..16.", "(16+1)/2.", "E = 8.5." ]
math
Answer: E = 8.5. Steps: 1. Mean of 1..16. 2. (16+1)/2. 3. E = 8.5.
probability
It claims every even number above 2 is a prime sum, verified far but unproven.
null
mat_0659
concept
en
What is the Goldbach conjecture?
[ "It claims every even number above 2 is a prime sum, verified far but unproven.", "So the answer stands: It claims every even number above 2 is a prime sum, verified far but unproven." ]
math
Answer: It claims every even number above 2 is a prime sum, verified far but unproven. Steps: 1. It claims every even number above 2 is a prime sum, verified far but unproven. 2. So the answer stands: It claims every even number above 2 is a prime sum, verified far but unproven.
number_theory
P(6,3) = 120.
null
mat_0660
worked_example
cs
Ukaž výpočet P(6,3).
[ "n(n−1)(n−2).", "6×5×4.", "= 120." ]
math
Answer: P(6,3) = 120. Steps: 1. n(n−1)(n−2). 2. 6×5×4. 3. = 120.
combinatorics
Parity splits numbers into even and odd, and tracking it often forces contradictions quickly.
null
mat_0661
concept
en
Why use parity arguments?
[ "Parity splits numbers into even and odd, and tracking it often forces contradictions quickly.", "So the answer stands: Parity splits numbers into even and odd, and tracking it often forces contradictions quickly." ]
math
Answer: Parity splits numbers into even and odd, and tracking it often forces contradictions quickly. Steps: 1. Parity splits numbers into even and odd, and tracking it often forces contradictions quickly. 2. So the answer stands: Parity splits numbers into even and odd, and tracking it often forces contradictions quic...
proofs
The derivative is 19.
{ "A": "17", "B": "19", "C": "21", "D": "23" }
mat_0662
multiple_choice
en
For f(x) = 3x² + 7x, find f'(2).
[ "f'(x) = 6x + 7.", "At 2: 19.", "Select option B." ]
math
Answer: 19 Steps: 1. f'(x) = 6x + 7. 2. At 2: 19. 3. Select option B. Answer: (B)
calculus
Stopa: 11.
null
mat_0663
worked_example
cs
Spočítej stopu matice [[5,0],[0,6]].
[ "Sečti diagonálu.", "5 + 6.", "= 11." ]
math
Answer: Stopa: 11. Steps: 1. Sečti diagonálu. 2. 5 + 6. 3. = 11.
linear_algebra
P(red) = 14/18.
null
mat_0664
worked_example
en
A bag holds 14 red and 4 blue marbles. Show P(red).
[ "Red: 14.", "Total: 18.", "P = 14/18." ]
math
Answer: P(red) = 14/18. Steps: 1. Red: 14. 2. Total: 18. 3. P = 14/18.
probability
gcd = 26.
null
mat_0665
worked_example
en
Compute gcd(52, 78) step by step.
[ "Factor: 52=4×13, 78=6×13.", "Common: 13×gcd(4,6).", "= 13×2 = 26." ]
math
Answer: gcd = 26. Steps: 1. Factor: 52=4×13, 78=6×13. 2. Common: 13×gcd(4,6). 3. = 13×2 = 26.
number_theory
C(8,3) = 56.
null
mat_0666
worked_example
cs
Ukaž výpočet C(8,3).
[ "n(n−1)(n−2)/6.", "8×7×6/6.", "= 56." ]
math
Answer: C(8,3) = 56. Steps: 1. n(n−1)(n−2)/6. 2. 8×7×6/6. 3. = 56.
combinatorics
Sum: 171.
null
mat_0667
worked_example
en
Prove by formula: find the sum 1 + 2 + ... + 18.
[ "Pair 1+18, 2+17, ...", "Use 18×19/2.", "= 171." ]
math
Answer: Sum: 171. Steps: 1. Pair 1+18, 2+17, ... 2. Use 18×19/2. 3. = 171.
proofs
Řeší neurčitosti 0/0 derivováním čitatele i jmenovatele.
null
mat_0668
concept
cs
Co je l'Hôpitalovo pravidlo?
[ "Řeší neurčitosti 0/0 derivováním čitatele i jmenovatele.", "Odpověď tedy platí: Řeší neurčitosti 0/0 derivováním čitatele i jmenovatele." ]
math
Answer: Řeší neurčitosti 0/0 derivováním čitatele i jmenovatele. Steps: 1. Řeší neurčitosti 0/0 derivováním čitatele i jmenovatele. 2. Odpověď tedy platí: Řeší neurčitosti 0/0 derivováním čitatele i jmenovatele.
calculus
Dot product: 115.
null
mat_0669
worked_example
en
Compute (15,14) · (3,5) step by step.
[ "Multiply components.", "15×3 + 14×5.", "= 115." ]
math
Answer: Dot product: 115. Steps: 1. Multiply components. 2. 15×3 + 14×5. 3. = 115.
linear_algebra
P(red) is 6/19.
{ "A": "13/19", "B": "6/20", "C": "6/19", "D": "7/19" }
mat_0670
multiple_choice
en
A bag holds 6 red and 13 blue marbles. What is P(red)?
[ "6 of 19.", "P = 6/19.", "Select option C." ]
math
Answer: 6/19 Steps: 1. 6 of 19. 2. P = 6/19. 3. Select option C. Answer: (C)
probability
The remainder is 0.
{ "A": "1", "B": "2", "C": "0", "D": "3" }
mat_0671
multiple_choice
en
Find (135) mod 9.
[ "135 ÷ 9.", "Remainder 0.", "Select option C." ]
math
Answer: 0 Steps: 1. 135 ÷ 9. 2. Remainder 0. 3. Select option C. Answer: (C)
number_theory
Odpověď je bijekce.
{ "A": "divoká mapa", "B": "bijekce", "C": "slepé hádání", "D": "mlhavá naděje" }
mat_0672
multiple_choice
cs
Vyber: co páruje množiny stejně?
[ "Inverze dokazuje velikost.", "Tedy: bijekce.", "Vyber možnost B." ]
math
Answer: bijekce Steps: 1. Inverze dokazuje velikost. 2. Tedy: bijekce. 3. Vyber možnost B. Answer: (B)
combinatorics
The value is 90.
{ "A": "90", "B": "88", "C": "92", "D": "94" }
mat_0673
multiple_choice
en
Compute N² + N for N = 9.
[ "9² + 9.", "Value = 90.", "Select option A." ]
math
Answer: 90 Steps: 1. 9² + 9. 2. Value = 90. 3. Select option A. Answer: (A)
proofs
It integrates over infinite bounds or singularities via limits, extending area to the unbounded.
null
mat_0674
concept
en
What is an improper integral?
[ "It integrates over infinite bounds or singularities via limits, extending area to the unbounded.", "So the answer stands: It integrates over infinite bounds or singularities via limits, extending area to the unbounded." ]
math
Answer: It integrates over infinite bounds or singularities via limits, extending area to the unbounded. Steps: 1. It integrates over infinite bounds or singularities via limits, extending area to the unbounded. 2. So the answer stands: It integrates over infinite bounds or singularities via limits, extending area to t...
calculus
Vlastní čísla odhalují směry natažení zobrazení.
null
mat_0675
concept
cs
Proč vlastní čísla?
[ "Vlastní čísla odhalují směry natažení zobrazení.", "Odpověď tedy platí: Vlastní čísla odhalují směry natažení zobrazení." ]
math
Answer: Vlastní čísla odhalují směry natažení zobrazení. Steps: 1. Vlastní čísla odhalují směry natažení zobrazení. 2. Odpověď tedy platí: Vlastní čísla odhalují směry natažení zobrazení.
linear_algebra
The answer is Expected value.
{ "A": "First outcome", "B": "Last digit", "C": "Wild guess", "D": "Expected value" }
mat_0676
multiple_choice
en
Choose: what averages long-run?
[ "Weighted by chance.", "So: Expected value.", "Select option D." ]
math
Answer: Expected value Steps: 1. Weighted by chance. 2. So: Expected value. 3. Select option D. Answer: (D)
probability
Pairs differing by 2 may be infinite, and bounded gaps progress nears the dream.
null
mat_0677
concept
en
Why twin primes?
[ "Pairs differing by 2 may be infinite, and bounded gaps progress nears the dream.", "So the answer stands: Pairs differing by 2 may be infinite, and bounded gaps progress nears the dream." ]
math
Answer: Pairs differing by 2 may be infinite, and bounded gaps progress nears the dream. Steps: 1. Pairs differing by 2 may be infinite, and bounded gaps progress nears the dream. 2. So the answer stands: Pairs differing by 2 may be infinite, and bounded gaps progress nears the dream.
number_theory
The answer is Linearity of expectation.
{ "A": "Linearity of expectation", "B": "Wild hope", "C": "Blind sum", "D": "Vague wish" }
mat_0678
multiple_choice
en
Choose: what adds regardless?
[ "Dependence ignored.", "So: Linearity of expectation.", "Select option A." ]
math
Answer: Linearity of expectation Steps: 1. Dependence ignored. 2. So: Linearity of expectation. 3. Select option A. Answer: (A)
combinatorics
Half: 105, so 210 is even.
null
mat_0679
worked_example
en
Show N² + N is even for N = 14 by computing its half.
[ "14² + 14 = 210.", "210 / 2 = 105.", "Integer, so even." ]
math
Answer: Half: 105, so 210 is even. Steps: 1. 14² + 14 = 210. 2. 210 / 2 = 105. 3. Integer, so even.
proofs
Limita: 10.
null
mat_0680
worked_example
cs
Vyčísli limitu (x² − 5²)/(x − 5) pro x → 5.
[ "Rozlož: (x−5)(x+5).", "Pokrať (x−5).", "Dosaď 5: 5+5 = 10." ]
math
Answer: Limita: 10. Steps: 1. Rozlož: (x−5)(x+5). 2. Pokrať (x−5). 3. Dosaď 5: 5+5 = 10.
calculus
Determinant: 270.
null
mat_0681
worked_example
en
Compute det [[16,1],[2,17]] step by step.
[ "ad − bc.", "16×17 − 1×2.", "= 270." ]
math
Answer: Determinant: 270. Steps: 1. ad − bc. 2. 16×17 − 1×2. 3. = 270.
linear_algebra
P = 1/18.
null
mat_0682
worked_example
en
A fair 18-sided die is rolled. Show P(one specific number).
[ "Favourable: 1.", "Possible: 18.", "P = 1/18." ]
math
Answer: P = 1/18. Steps: 1. Favourable: 1. 2. Possible: 18. 3. P = 1/18.
probability
Primes thin like n/log n, describing their large-scale density precisely.
null
mat_0683
concept
en
What is the prime number theorem?
[ "Primes thin like n/log n, describing their large-scale density precisely.", "So the answer stands: Primes thin like n/log n, describing their large-scale density precisely." ]
math
Answer: Primes thin like n/log n, describing their large-scale density precisely. Steps: 1. Primes thin like n/log n, describing their large-scale density precisely. 2. So the answer stands: Primes thin like n/log n, describing their large-scale density precisely.
number_theory
C(9,2) is 36.
{ "A": "27", "B": "36", "C": "45", "D": "54" }
mat_0684
multiple_choice
en
Compute C(9,2).
[ "9×8/2.", "= 36.", "Select option B." ]
math
Answer: 36 Steps: 1. 9×8/2. 2. = 36. 3. Select option B. Answer: (B)
combinatorics
Polovina: 15, číslo 30 je sudé.
null
mat_0685
worked_example
cs
Ukaž, že N² + N je sudé pro N = 5, výpočtem poloviny.
[ "5² + 5 = 30.", "30 / 2 = 15.", "Celé číslo, tedy sudé." ]
math
Answer: Polovina: 15, číslo 30 je sudé. Steps: 1. 5² + 5 = 30. 2. 30 / 2 = 15. 3. Celé číslo, tedy sudé.
proofs
Integral: 3375.
null
mat_0686
worked_example
en
Evaluate the integral of 3x² from 0 to 15.
[ "Antiderivative: x³.", "Evaluate 0 to 15.", "15³ − 0 = 3375." ]
math
Answer: Integral: 3375. Steps: 1. Antiderivative: x³. 2. Evaluate 0 to 15. 3. 15³ − 0 = 3375.
calculus
Odpověď je skalární součin.
{ "A": "skalární součin", "B": "divoký odhad", "C": "slepý součet", "D": "slepá naděje" }
mat_0687
multiple_choice
cs
Vyber: co měří úhly?
[ "Nula znamená kolmost.", "Tedy: skalární součin.", "Vyber možnost A." ]
math
Answer: skalární součin Steps: 1. Nula znamená kolmost. 2. Tedy: skalární součin. 3. Vyber možnost A. Answer: (A)
linear_algebra
Regression fits lines minimizing squared error, predicting responses from predictors.
null
mat_0688
concept
en
Why regression?
[ "Regression fits lines minimizing squared error, predicting responses from predictors.", "So the answer stands: Regression fits lines minimizing squared error, predicting responses from predictors." ]
math
Answer: Regression fits lines minimizing squared error, predicting responses from predictors. Steps: 1. Regression fits lines minimizing squared error, predicting responses from predictors. 2. So the answer stands: Regression fits lines minimizing squared error, predicting responses from predictors.
probability
Remainder: 3.
null
mat_0689
worked_example
en
Compute (171) mod 7.
[ "Divide 171 by 7.", "7×24 = 168.", "171 − 168 = 3." ]
math
Answer: Remainder: 3. Steps: 1. Divide 171 by 7. 2. 7×24 = 168. 3. 171 − 168 = 3.
number_theory
P(15,3) = 2730.
null
mat_0690
worked_example
en
Show the computation of P(15,3).
[ "n(n−1)(n−2).", "15×14×13.", "= 2730." ]
math
Answer: P(15,3) = 2730. Steps: 1. n(n−1)(n−2). 2. 15×14×13. 3. = 2730.
combinatorics
De Morganovy zákony převracejí a/nebo při negaci.
null
mat_0691
concept
cs
Co je De Morganův zákon?
[ "De Morganovy zákony převracejí a/nebo při negaci.", "Odpověď tedy platí: De Morganovy zákony převracejí a/nebo při negaci." ]
math
Answer: De Morganovy zákony převracejí a/nebo při negaci. Steps: 1. De Morganovy zákony převracejí a/nebo při negaci. 2. Odpověď tedy platí: De Morganovy zákony převracejí a/nebo při negaci.
proofs
The integral is 343.
{ "A": "336", "B": "350", "C": "343", "D": "357" }
mat_0692
multiple_choice
en
Compute the integral of 3x² from 0 to 7.
[ "Antiderivative x³.", "7³ = 343.", "Select option C." ]
math
Answer: 343 Steps: 1. Antiderivative x³. 2. 7³ = 343. 3. Select option C. Answer: (C)
calculus
Skalární součin: 27.
null
mat_0693
worked_example
cs
Spočítej (4,3) · (3,5) krok za krokem.
[ "Násob složky.", "4×3 + 3×5.", "= 27." ]
math
Answer: Skalární součin: 27. Steps: 1. Násob složky. 2. 4×3 + 3×5. 3. = 27.
linear_algebra
The answer is Independent trials.
{ "A": "Independent trials", "B": "Old coins", "C": "Tired dice", "D": "Worn cards" }
mat_0694
multiple_choice
en
Choose: what has no memory?
[ "Streaks mean nothing.", "So: Independent trials.", "Select option A." ]
math
Answer: Independent trials Steps: 1. Streaks mean nothing. 2. So: Independent trials. 3. Select option A. Answer: (A)
probability
lcm = 16.
null
mat_0695
worked_example
en
Compute lcm(16, 8) step by step.
[ "gcd(16,8) = 8.", "16×8/8.", "= 16." ]
math
Answer: lcm = 16. Steps: 1. gcd(16,8) = 8. 2. 16×8/8. 3. = 16.
number_theory
It finds maxima under forbidden patterns, like most edges without triangles.
null
mat_0696
concept
en
What is extremal combinatorics?
[ "It finds maxima under forbidden patterns, like most edges without triangles.", "So the answer stands: It finds maxima under forbidden patterns, like most edges without triangles." ]
math
Answer: It finds maxima under forbidden patterns, like most edges without triangles. Steps: 1. It finds maxima under forbidden patterns, like most edges without triangles. 2. So the answer stands: It finds maxima under forbidden patterns, like most edges without triangles.
combinatorics
An invariant is a quantity unchanged by allowed moves, so differing invariants prove targets unreachable.
null
mat_0697
concept
en
What is an invariant?
[ "An invariant is a quantity unchanged by allowed moves, so differing invariants prove targets unreachable.", "So the answer stands: An invariant is a quantity unchanged by allowed moves, so differing invariants prove targets unreachable." ]
math
Answer: An invariant is a quantity unchanged by allowed moves, so differing invariants prove targets unreachable. Steps: 1. An invariant is a quantity unchanged by allowed moves, so differing invariants prove targets unreachable. 2. So the answer stands: An invariant is a quantity unchanged by allowed moves, so differi...
proofs
The limit is 14.
{ "A": "12", "B": "16", "C": "18", "D": "14" }
mat_0698
multiple_choice
en
Find the limit of (x² − 7²)/(x − 7) as x → 7.
[ "Factor (x−7)(x+7).", "Cancel, get 2×7 = 14.", "Select option D." ]
math
Answer: 14 Steps: 1. Factor (x−7)(x+7). 2. Cancel, get 2×7 = 14. 3. Select option D. Answer: (D)
calculus
The answer is SVD.
{ "A": "SVD", "B": "Lucky cut", "C": "Blind split", "D": "Wild guess" }
mat_0699
multiple_choice
en
Choose: what splits any matrix?
[ "Rotations plus scalings.", "So: SVD.", "Select option A." ]
math
Answer: SVD Steps: 1. Rotations plus scalings. 2. So: SVD. 3. Select option A. Answer: (A)
linear_algebra
E = 9.
null
mat_0700
worked_example
en
Compute E of a uniform draw from {1..17}.
[ "Mean of 1..17.", "(17+1)/2.", "E = 9." ]
math
Answer: E = 9. Steps: 1. Mean of 1..17. 2. (17+1)/2. 3. E = 9.
probability
The lcm is 18.
{ "A": "16", "B": "20", "C": "22", "D": "18" }
mat_0701
multiple_choice
en
Find lcm(9, 6).
[ "9×6/gcd.", "lcm = 18.", "Select option D." ]
math
Answer: 18 Steps: 1. 9×6/gcd. 2. lcm = 18. 3. Select option D. Answer: (D)
number_theory
C(8,2) = 28.
null
mat_0702
worked_example
cs
Ukaž výpočet C(8,2).
[ "Vzorec n(n−1)/2.", "8×7/2.", "= 28." ]
math
Answer: C(8,2) = 28. Steps: 1. Vzorec n(n−1)/2. 2. 8×7/2. 3. = 28.
combinatorics
Formal induction states base and step explicitly, catching hidden gaps in recursive reasoning.
null
mat_0703
concept
en
Why formalize induction?
[ "Formal induction states base and step explicitly, catching hidden gaps in recursive reasoning.", "So the answer stands: Formal induction states base and step explicitly, catching hidden gaps in recursive reasoning." ]
math
Answer: Formal induction states base and step explicitly, catching hidden gaps in recursive reasoning. Steps: 1. Formal induction states base and step explicitly, catching hidden gaps in recursive reasoning. 2. So the answer stands: Formal induction states base and step explicitly, catching hidden gaps in recursive rea...
proofs
Parametrization traces curves by a parameter, simplifying motion and arc-length questions.
null
mat_0704
concept
en
Why parametrize curves?
[ "Parametrization traces curves by a parameter, simplifying motion and arc-length questions.", "So the answer stands: Parametrization traces curves by a parameter, simplifying motion and arc-length questions." ]
math
Answer: Parametrization traces curves by a parameter, simplifying motion and arc-length questions. Steps: 1. Parametrization traces curves by a parameter, simplifying motion and arc-length questions. 2. So the answer stands: Parametrization traces curves by a parameter, simplifying motion and arc-length questions.
calculus
Trace: 35.
null
mat_0705
worked_example
en
Compute the trace of [[17,0],[0,18]].
[ "Sum diagonal.", "17 + 18.", "= 35." ]
math
Answer: Trace: 35. Steps: 1. Sum diagonal. 2. 17 + 18. 3. = 35.
linear_algebra
The probability is 1/11.
{ "A": "1/10", "B": "1/11", "C": "1/12", "D": "2/11" }
mat_0706
multiple_choice
en
A fair 11-sided die is rolled. What is the probability of one specific number?
[ "1 face of 11.", "P = 1/11.", "Select option B." ]
math
Answer: 1/11 Steps: 1. 1 face of 11. 2. P = 1/11. 3. Select option B. Answer: (B)
probability
gcd = 28.
null
mat_0707
worked_example
en
Compute gcd(56, 84) step by step.
[ "Factor: 56=4×14, 84=6×14.", "Common: 14×gcd(4,6).", "= 14×2 = 28." ]
math
Answer: gcd = 28. Steps: 1. Factor: 56=4×14, 84=6×14. 2. Common: 14×gcd(4,6). 3. = 14×2 = 28.
number_theory
Počítá rozdělení stejných předmětů do krabic.
null
mat_0708
concept
cs
Proč metoda hvězdiček?
[ "Počítá rozdělení stejných předmětů do krabic.", "Odpověď tedy platí: Počítá rozdělení stejných předmětů do krabic." ]
math
Answer: Počítá rozdělení stejných předmětů do krabic. Steps: 1. Počítá rozdělení stejných předmětů do krabic. 2. Odpověď tedy platí: Počítá rozdělení stejných předmětů do krabic.
combinatorics
Rows: 32768.
null
mat_0709
worked_example
en
A proof checks all cases of 15 boolean variables. How many rows?
[ "2 choices each.", "2^15 = 32768." ]
math
Answer: Rows: 32768. Steps: 1. 2 choices each. 2. 2^15 = 32768.
proofs
Arc length integrates speed along a curve, giving the exact distance travelled.
null
mat_0710
concept
en
What is arc length?
[ "Arc length integrates speed along a curve, giving the exact distance travelled.", "So the answer stands: Arc length integrates speed along a curve, giving the exact distance travelled." ]
math
Answer: Arc length integrates speed along a curve, giving the exact distance travelled. Steps: 1. Arc length integrates speed along a curve, giving the exact distance travelled. 2. So the answer stands: Arc length integrates speed along a curve, giving the exact distance travelled.
calculus
Determinant: 28.
null
mat_0711
worked_example
cs
Spočítej det [[5,1],[2,6]] krok za krokem.
[ "ad − bc.", "5×6 − 1×2.", "= 28." ]
math
Answer: Determinant: 28. Steps: 1. ad − bc. 2. 5×6 − 1×2. 3. = 28.
linear_algebra
P(red) = 15/19.
null
mat_0712
worked_example
en
A bag holds 15 red and 4 blue marbles. Show P(red).
[ "Red: 15.", "Total: 19.", "P = 15/19." ]
math
Answer: P(red) = 15/19. Steps: 1. Red: 15. 2. Total: 19. 3. P = 15/19.
probability
It crosses multiples to list primes fast, the classic prime-finding engine.
null
mat_0713
concept
en
Why sieve of Eratosthenes?
[ "It crosses multiples to list primes fast, the classic prime-finding engine.", "So the answer stands: It crosses multiples to list primes fast, the classic prime-finding engine." ]
math
Answer: It crosses multiples to list primes fast, the classic prime-finding engine. Steps: 1. It crosses multiples to list primes fast, the classic prime-finding engine. 2. So the answer stands: It crosses multiples to list primes fast, the classic prime-finding engine.
number_theory
C(17,3) = 680.
null
mat_0714
worked_example
en
Show the computation of C(17,3).
[ "n(n−1)(n−2)/6.", "17×16×15/6.", "= 680." ]
math
Answer: C(17,3) = 680. Steps: 1. n(n−1)(n−2)/6. 2. 17×16×15/6. 3. = 680.
combinatorics
Exhaustion checks every case by hand or computer, and it works when the case list is finite.
null
mat_0715
concept
en
What is proof by exhaustion?
[ "Exhaustion checks every case by hand or computer, and it works when the case list is finite.", "So the answer stands: Exhaustion checks every case by hand or computer, and it works when the case list is finite." ]
math
Answer: Exhaustion checks every case by hand or computer, and it works when the case list is finite. Steps: 1. Exhaustion checks every case by hand or computer, and it works when the case list is finite. 2. So the answer stands: Exhaustion checks every case by hand or computer, and it works when the case list is finite...
proofs
The gradient points to steepest ascent, guiding optimization and physics on surfaces.
null
mat_0716
concept
en
Why learn gradient?
[ "The gradient points to steepest ascent, guiding optimization and physics on surfaces.", "So the answer stands: The gradient points to steepest ascent, guiding optimization and physics on surfaces." ]
math
Answer: The gradient points to steepest ascent, guiding optimization and physics on surfaces. Steps: 1. The gradient points to steepest ascent, guiding optimization and physics on surfaces. 2. So the answer stands: The gradient points to steepest ascent, guiding optimization and physics on surfaces.
calculus
Dot product: 123.
null
mat_0717
worked_example
en
Compute (16,15) · (3,5) step by step.
[ "Multiply components.", "16×3 + 15×5.", "= 123." ]
math
Answer: Dot product: 123. Steps: 1. Multiply components. 2. 16×3 + 15×5. 3. = 123.
linear_algebra
P = 1/19.
null
mat_0718
worked_example
en
A fair 19-sided die is rolled. Show P(one specific number).
[ "Favourable: 1.", "Possible: 19.", "P = 1/19." ]
math
Answer: P = 1/19. Steps: 1. Favourable: 1. 2. Possible: 19. 3. P = 1/19.
probability
It tests divisors up to sqrt(n), simple and sure for small primality checks.
null
mat_0719
concept
en
What is trial division?
[ "It tests divisors up to sqrt(n), simple and sure for small primality checks.", "So the answer stands: It tests divisors up to sqrt(n), simple and sure for small primality checks." ]
math
Answer: It tests divisors up to sqrt(n), simple and sure for small primality checks. Steps: 1. It tests divisors up to sqrt(n), simple and sure for small primality checks. 2. So the answer stands: It tests divisors up to sqrt(n), simple and sure for small primality checks.
number_theory
Random choices prove existence, showing desired objects occur with positive chance.
null
mat_0720
concept
en
Why probabilistic method?
[ "Random choices prove existence, showing desired objects occur with positive chance.", "So the answer stands: Random choices prove existence, showing desired objects occur with positive chance." ]
math
Answer: Random choices prove existence, showing desired objects occur with positive chance. Steps: 1. Random choices prove existence, showing desired objects occur with positive chance. 2. So the answer stands: Random choices prove existence, showing desired objects occur with positive chance.
combinatorics
Short proofs are easier to check and teach, though finding them often takes more insight.
null
mat_0721
concept
en
Why prefer short proofs?
[ "Short proofs are easier to check and teach, though finding them often takes more insight.", "So the answer stands: Short proofs are easier to check and teach, though finding them often takes more insight." ]
math
Answer: Short proofs are easier to check and teach, though finding them often takes more insight. Steps: 1. Short proofs are easier to check and teach, though finding them often takes more insight. 2. So the answer stands: Short proofs are easier to check and teach, though finding them often takes more insight.
proofs
The derivative is 14.
{ "A": "12", "B": "16", "C": "14", "D": "18" }
mat_0722
multiple_choice
en
For f(x) = 1x² + 8x, find f'(3).
[ "f'(x) = 2x + 8.", "At 3: 14.", "Select option C." ]
math
Answer: 14 Steps: 1. f'(x) = 2x + 8. 2. At 3: 14. 3. Select option C. Answer: (C)
calculus
The determinant is 48.
{ "A": "45", "B": "48", "C": "51", "D": "54" }
mat_0723
multiple_choice
en
Find the determinant of [[6,2],[3,9]].
[ "6×9 − 2×3.", "Det = 48.", "Select option B." ]
math
Answer: 48 Steps: 1. 6×9 − 2×3. 2. Det = 48. 3. Select option B. Answer: (B)
linear_algebra
E = 9.5.
null
mat_0724
worked_example
en
Compute E of a uniform draw from {1..18}.
[ "Mean of 1..18.", "(18+1)/2.", "E = 9.5." ]
math
Answer: E = 9.5. Steps: 1. Mean of 1..18. 2. (18+1)/2. 3. E = 9.5.
probability
The gcd is 24.
{ "A": "21", "B": "27", "C": "24", "D": "30" }
mat_0725
multiple_choice
en
Find gcd(48, 72).
[ "Factor 3 out twice.", "gcd = 24.", "Select option C." ]
math
Answer: 24 Steps: 1. Factor 3 out twice. 2. gcd = 24. 3. Select option C. Answer: (C)
number_theory
C(17,2) = 136.
null
mat_0726
worked_example
en
Show the computation of C(17,2).
[ "Formula n(n−1)/2.", "17×16/2.", "= 136." ]
math
Answer: C(17,2) = 136. Steps: 1. Formula n(n−1)/2. 2. 17×16/2. 3. = 136.
combinatorics
The table has 512 rows.
{ "A": "510", "B": "514", "C": "516", "D": "512" }
mat_0727
multiple_choice
en
How many rows does a truth table with 9 variables have?
[ "2^9 rows.", "Total: 512.", "Select option D." ]
math
Answer: 512 Steps: 1. 2^9 rows. 2. Total: 512. 3. Select option D. Answer: (D)
proofs
It sums over regions in the plane, computing volumes under surfaces slice by slice.
null
mat_0728
concept
en
What is a double integral?
[ "It sums over regions in the plane, computing volumes under surfaces slice by slice.", "So the answer stands: It sums over regions in the plane, computing volumes under surfaces slice by slice." ]
math
Answer: It sums over regions in the plane, computing volumes under surfaces slice by slice. Steps: 1. It sums over regions in the plane, computing volumes under surfaces slice by slice. 2. So the answer stands: It sums over regions in the plane, computing volumes under surfaces slice by slice.
calculus
The trace is 17.
{ "A": "15", "B": "19", "C": "17", "D": "21" }
mat_0729
multiple_choice
en
Find the trace of [[7,1],[2,10]].
[ "7 + 10.", "Trace = 17.", "Select option C." ]
math
Answer: 17 Steps: 1. 7 + 10. 2. Trace = 17. 3. Select option C. Answer: (C)
linear_algebra
P(red) = 16/20.
null
mat_0730
worked_example
en
A bag holds 16 red and 4 blue marbles. Show P(red).
[ "Red: 16.", "Total: 20.", "P = 16/20." ]
math
Answer: P(red) = 16/20. Steps: 1. Red: 16. 2. Total: 20. 3. P = 16/20.
probability
The remainder is 7.
{ "A": "8", "B": "0", "C": "1", "D": "7" }
mat_0731
multiple_choice
en
Find (142) mod 9.
[ "142 ÷ 9.", "Remainder 7.", "Select option D." ]
math
Answer: 7 Steps: 1. 142 ÷ 9. 2. Remainder 7. 3. Select option D. Answer: (D)
number_theory
P(16,3) = 3360.
null
mat_0732
worked_example
en
Show the computation of P(16,3).
[ "n(n−1)(n−2).", "16×15×14.", "= 3360." ]
math
Answer: P(16,3) = 3360. Steps: 1. n(n−1)(n−2). 2. 16×15×14. 3. = 3360.
combinatorics
Odpověď je základní případ.
{ "A": "složitá notace", "B": "dlouhé řetězy", "C": "velká čísla", "D": "základní případ" }
mat_0733
multiple_choice
cs
Vyber: co kotví indukci?
[ "Bez základu řetěz nic nedokazuje.", "Tedy: základní případ.", "Vyber možnost D." ]
math
Answer: základní případ Steps: 1. Bez základu řetěz nic nedokazuje. 2. Tedy: základní případ. 3. Vyber možnost D. Answer: (D)
proofs
Limit: 30.
null
mat_0734
worked_example
en
Evaluate the limit of (x² − 15²)/(x − 15) as x → 15.
[ "Factor: (x−15)(x+15).", "Cancel (x−15).", "Plug 15: 15+15 = 30." ]
math
Answer: Limit: 30. Steps: 1. Factor: (x−15)(x+15). 2. Cancel (x−15). 3. Plug 15: 15+15 = 30.
calculus
New bases simplify matrices, revealing hidden diagonal or triangular structure.
null
mat_0735
concept
en
Why change basis?
[ "New bases simplify matrices, revealing hidden diagonal or triangular structure.", "So the answer stands: New bases simplify matrices, revealing hidden diagonal or triangular structure." ]
math
Answer: New bases simplify matrices, revealing hidden diagonal or triangular structure. Steps: 1. New bases simplify matrices, revealing hidden diagonal or triangular structure. 2. So the answer stands: New bases simplify matrices, revealing hidden diagonal or triangular structure.
linear_algebra
Overfitting memorizes noise instead of patterns, failing on new data despite perfect training.
null
mat_0736
concept
en
What is overfitting?
[ "Overfitting memorizes noise instead of patterns, failing on new data despite perfect training.", "So the answer stands: Overfitting memorizes noise instead of patterns, failing on new data despite perfect training." ]
math
Answer: Overfitting memorizes noise instead of patterns, failing on new data despite perfect training. Steps: 1. Overfitting memorizes noise instead of patterns, failing on new data despite perfect training. 2. So the answer stands: Overfitting memorizes noise instead of patterns, failing on new data despite perfect tr...
probability
Remainder: 0.
null
mat_0737
worked_example
en
Compute (182) mod 7.
[ "Divide 182 by 7.", "7×26 = 182.", "182 − 182 = 0." ]
math
Answer: Remainder: 0. Steps: 1. Divide 182 by 7. 2. 7×26 = 182. 3. 182 − 182 = 0.
number_theory
P(8,2) is 56.
{ "A": "48", "B": "64", "C": "56", "D": "72" }
mat_0738
multiple_choice
en
Compute P(8,2).
[ "8×7.", "= 56.", "Select option C." ]
math
Answer: 56 Steps: 1. 8×7. 2. = 56. 3. Select option C. Answer: (C)
combinatorics
The sum is 78.
{ "A": "78", "B": "66", "C": "90", "D": "102" }
mat_0739
multiple_choice
en
What is the sum 1 + 2 + ... + 12?
[ "12×13/2.", "Sum = 78.", "Select option A." ]
math
Answer: 78 Steps: 1. 12×13/2. 2. Sum = 78. 3. Select option A. Answer: (A)
proofs
Limita je 6.
{ "A": "4", "B": "8", "C": "10", "D": "6" }
mat_0740
multiple_choice
cs
Vypočítej limitu (x² − 3²)/(x − 3) pro x → 3.
[ "Rozlož (x−3)(x+3).", "Pokrať, dostaneš 2×3 = 6.", "Vyber možnost D." ]
math
Answer: 6 Steps: 1. Rozlož (x−3)(x+3). 2. Pokrať, dostaneš 2×3 = 6. 3. Vyber možnost D. Answer: (D)
calculus
The dot product is 46.
{ "A": "42", "B": "50", "C": "54", "D": "46" }
mat_0741
multiple_choice
en
Find the dot product (6,7) · (3,4).
[ "6×3 + 7×4.", "Product = 46.", "Select option D." ]
math
Answer: 46 Steps: 1. 6×3 + 7×4. 2. Product = 46. 3. Select option D. Answer: (D)
linear_algebra
P(červená) je 3/10.
{ "A": "7/10", "B": "3/11", "C": "4/10", "D": "3/10" }
mat_0742
multiple_choice
cs
Sáček má 3 červených a 7 modrých kuliček. Jaká je P(červená)?
[ "3 z 10.", "P = 3/10.", "Vyber možnost D." ]
math
Answer: 3/10 Steps: 1. 3 z 10. 2. P = 3/10. 3. Vyber možnost D. Answer: (D)
probability
lcm = 136.
null
mat_0743
worked_example
en
Compute lcm(17, 8) step by step.
[ "gcd(17,8) = 1.", "17×8/1.", "= 136." ]
math
Answer: lcm = 136. Steps: 1. gcd(17,8) = 1. 2. 17×8/1. 3. = 136.
number_theory
C(10,3) is 120.
{ "A": "110", "B": "130", "C": "140", "D": "120" }
mat_0744
multiple_choice
en
Compute C(10,3).
[ "10×9×8/6.", "= 120.", "Select option D." ]
math
Answer: 120 Steps: 1. 10×9×8/6. 2. = 120. 3. Select option D. Answer: (D)
combinatorics
A non-constructive proof shows existence without exhibiting the object, often via counting or contradiction.
null
mat_0745
concept
en
What is a non-constructive proof?
[ "A non-constructive proof shows existence without exhibiting the object, often via counting or contradiction.", "So the answer stands: A non-constructive proof shows existence without exhibiting the object, often via counting or contradiction." ]
math
Answer: A non-constructive proof shows existence without exhibiting the object, often via counting or contradiction. Steps: 1. A non-constructive proof shows existence without exhibiting the object, often via counting or contradiction. 2. So the answer stands: A non-constructive proof shows existence without exhibiting...
proofs
f'(3) = 32.
null
mat_0746
worked_example
en
For f(x) = 3x² + 14x, compute f'(3) step by step.
[ "f'(x) = 6x + 14.", "Plug x = 3.", "6×3 + 14 = 32." ]
math
Answer: f'(3) = 32. Steps: 1. f'(x) = 6x + 14. 2. Plug x = 3. 3. 6×3 + 14 = 32.
calculus
Determinant je 4.
{ "A": "1", "B": "4", "C": "7", "D": "10" }
mat_0747
multiple_choice
cs
Vypočítej determinant matice [[2,2],[3,5]].
[ "2×5 − 2×3.", "Det = 4.", "Vyber možnost B." ]
math
Answer: 4 Steps: 1. 2×5 − 2×3. 2. Det = 4. 3. Vyber možnost B. Answer: (B)
linear_algebra
It tests models on held-out data, honestly estimating real-world performance.
null
mat_0748
concept
en
Why cross-validate?
[ "It tests models on held-out data, honestly estimating real-world performance.", "So the answer stands: It tests models on held-out data, honestly estimating real-world performance." ]
math
Answer: It tests models on held-out data, honestly estimating real-world performance. Steps: 1. It tests models on held-out data, honestly estimating real-world performance. 2. So the answer stands: It tests models on held-out data, honestly estimating real-world performance.
probability
The lcm is 30.
{ "A": "30", "B": "28", "C": "32", "D": "34" }
mat_0749
multiple_choice
en
Find lcm(10, 6).
[ "10×6/gcd.", "lcm = 30.", "Select option A." ]
math
Answer: 30 Steps: 1. 10×6/gcd. 2. lcm = 30. 3. Select option A. Answer: (A)
number_theory
C(10,2) is 45.
{ "A": "35", "B": "55", "C": "45", "D": "65" }
mat_0750
multiple_choice
en
Compute C(10,2).
[ "10×9/2.", "= 45.", "Select option C." ]
math
Answer: 45 Steps: 1. 10×9/2. 2. = 45. 3. Select option C. Answer: (C)
combinatorics