answer
string
choices
dict
id
string
kind
string
lang
string
question
string
steps
list
subject
string
text
string
topic
string
Techniques transfer across fields, so mastering induction and contradiction unlocks all of mathematics.
null
mat_0751
concept
en
Why study proof techniques?
[ "Techniques transfer across fields, so mastering induction and contradiction unlocks all of mathematics.", "So the answer stands: Techniques transfer across fields, so mastering induction and contradiction unlocks all of mathematics." ]
math
Answer: Techniques transfer across fields, so mastering induction and contradiction unlocks all of mathematics. Steps: 1. Techniques transfer across fields, so mastering induction and contradiction unlocks all of mathematics. 2. So the answer stands: Techniques transfer across fields, so mastering induction and contrad...
proofs
The integral is 512.
{ "A": "504", "B": "520", "C": "528", "D": "512" }
mat_0752
multiple_choice
en
Compute the integral of 3x² from 0 to 8.
[ "Antiderivative x³.", "8³ = 512.", "Select option D." ]
math
Answer: 512 Steps: 1. Antiderivative x³. 2. 8³ = 512. 3. Select option D. Answer: (D)
calculus
Similar matrices represent one map in different bases, sharing eigenvalues and determinant.
null
mat_0753
concept
en
What is similarity?
[ "Similar matrices represent one map in different bases, sharing eigenvalues and determinant.", "So the answer stands: Similar matrices represent one map in different bases, sharing eigenvalues and determinant." ]
math
Answer: Similar matrices represent one map in different bases, sharing eigenvalues and determinant. Steps: 1. Similar matrices represent one map in different bases, sharing eigenvalues and determinant. 2. So the answer stands: Similar matrices represent one map in different bases, sharing eigenvalues and determinant.
linear_algebra
P = 1/20.
null
mat_0754
worked_example
en
A fair 20-sided die is rolled. Show P(one specific number).
[ "Favourable: 1.", "Possible: 20.", "P = 1/20." ]
math
Answer: P = 1/20. Steps: 1. Favourable: 1. 2. Possible: 20. 3. P = 1/20.
probability
The gcd is 27.
{ "A": "24", "B": "30", "C": "33", "D": "27" }
mat_0755
multiple_choice
en
Find gcd(54, 81).
[ "Factor 3 out twice.", "gcd = 27.", "Select option D." ]
math
Answer: 27 Steps: 1. Factor 3 out twice. 2. gcd = 27. 3. Select option D. Answer: (D)
number_theory
Expectations add regardless of dependence, simplifying random counts hugely.
null
mat_0756
concept
en
What is linearity of expectation?
[ "Expectations add regardless of dependence, simplifying random counts hugely.", "So the answer stands: Expectations add regardless of dependence, simplifying random counts hugely." ]
math
Answer: Expectations add regardless of dependence, simplifying random counts hugely. Steps: 1. Expectations add regardless of dependence, simplifying random counts hugely. 2. So the answer stands: Expectations add regardless of dependence, simplifying random counts hugely.
combinatorics
Řádků: 64.
null
mat_0757
worked_example
cs
Důkaz prochází všechny případy 6 booleovských proměnných. Kolik řádků?
[ "2 volby každá.", "2^6 = 64." ]
math
Answer: Řádků: 64. Steps: 1. 2 volby každá. 2. 2^6 = 64.
proofs
The limit is 16.
{ "A": "16", "B": "14", "C": "18", "D": "20" }
mat_0758
multiple_choice
en
Find the limit of (x² − 8²)/(x − 8) as x → 8.
[ "Factor (x−8)(x+8).", "Cancel, get 2×8 = 16.", "Select option A." ]
math
Answer: 16 Steps: 1. Factor (x−8)(x+8). 2. Cancel, get 2×8 = 16. 3. Select option A. Answer: (A)
calculus
Determinant: 304.
null
mat_0759
worked_example
en
Compute det [[17,1],[2,18]] step by step.
[ "ad − bc.", "17×18 − 1×2.", "= 304." ]
math
Answer: Determinant: 304. Steps: 1. ad − bc. 2. 17×18 − 1×2. 3. = 304.
linear_algebra
The expected value is 5.
{ "A": "6", "B": "4", "C": "5", "D": "7" }
mat_0760
multiple_choice
en
Find the expected value of a uniform draw from {1..9}.
[ "(9+1)/2.", "E = 5.", "Select option C." ]
math
Answer: 5 Steps: 1. (9+1)/2. 2. E = 5. 3. Select option C. Answer: (C)
probability
phi(n) počítá čísla menší než n nesoudělná s ním.
null
mat_0761
concept
cs
Co je Eulerova funkce?
[ "phi(n) počítá čísla menší než n nesoudělná s ním.", "Odpověď tedy platí: phi(n) počítá čísla menší než n nesoudělná s ním." ]
math
Answer: phi(n) počítá čísla menší než n nesoudělná s ním. Steps: 1. phi(n) počítá čísla menší než n nesoudělná s ním. 2. Odpověď tedy platí: phi(n) počítá čísla menší než n nesoudělná s ním.
number_theory
C(18,3) = 816.
null
mat_0762
worked_example
en
Show the computation of C(18,3).
[ "n(n−1)(n−2)/6.", "18×17×16/6.", "= 816." ]
math
Answer: C(18,3) = 816. Steps: 1. n(n−1)(n−2)/6. 2. 18×17×16/6. 3. = 816.
combinatorics
Sum: 190.
null
mat_0763
worked_example
en
Prove by formula: find the sum 1 + 2 + ... + 19.
[ "Pair 1+19, 2+18, ...", "Use 19×20/2.", "= 190." ]
math
Answer: Sum: 190. Steps: 1. Pair 1+19, 2+18, ... 2. Use 19×20/2. 3. = 190.
proofs
Integral: 4096.
null
mat_0764
worked_example
en
Evaluate the integral of 3x² from 0 to 16.
[ "Antiderivative: x³.", "Evaluate 0 to 16.", "16³ − 0 = 4096." ]
math
Answer: Integral: 4096. Steps: 1. Antiderivative: x³. 2. Evaluate 0 to 16. 3. 16³ − 0 = 4096.
calculus
Stopa: 13.
null
mat_0765
worked_example
cs
Spočítej stopu matice [[6,0],[0,7]].
[ "Sečti diagonálu.", "6 + 7.", "= 13." ]
math
Answer: Stopa: 13. Steps: 1. Sečti diagonálu. 2. 6 + 7. 3. = 13.
linear_algebra
P(červená) = 5/9.
null
mat_0766
worked_example
cs
Sáček má 5 červených a 4 modré kuličky. Ukaž P(červená).
[ "Červené: 5.", "Celkem: 9.", "P = 5/9." ]
math
Answer: P(červená) = 5/9. Steps: 1. Červené: 5. 2. Celkem: 9. 3. P = 5/9.
probability
gcd = 30.
null
mat_0767
worked_example
en
Compute gcd(60, 90) step by step.
[ "Factor: 60=4×15, 90=6×15.", "Common: 15×gcd(4,6).", "= 15×2 = 30." ]
math
Answer: gcd = 30. Steps: 1. Factor: 60=4×15, 90=6×15. 2. Common: 15×gcd(4,6). 3. = 15×2 = 30.
number_theory
C(18,2) = 153.
null
mat_0768
worked_example
en
Show the computation of C(18,2).
[ "Formula n(n−1)/2.", "18×17/2.", "= 153." ]
math
Answer: C(18,2) = 153. Steps: 1. Formula n(n−1)/2. 2. 18×17/2. 3. = 153.
combinatorics
Half: 120, so 240 is even.
null
mat_0769
worked_example
en
Show N² + N is even for N = 15 by computing its half.
[ "15² + 15 = 240.", "240 / 2 = 120.", "Integer, so even." ]
math
Answer: Half: 120, so 240 is even. Steps: 1. 15² + 15 = 240. 2. 240 / 2 = 120. 3. Integer, so even.
proofs
The derivative is 25.
{ "A": "23", "B": "27", "C": "29", "D": "25" }
mat_0770
multiple_choice
en
For f(x) = 2x² + 9x, find f'(4).
[ "f'(x) = 4x + 9.", "At 4: 25.", "Select option D." ]
math
Answer: 25 Steps: 1. f'(x) = 4x + 9. 2. At 4: 25. 3. Select option D. Answer: (D)
calculus
Skalární součin: 35.
null
mat_0771
worked_example
cs
Spočítej (5,4) · (3,5) krok za krokem.
[ "Násob složky.", "5×3 + 4×5.", "= 35." ]
math
Answer: Skalární součin: 35. Steps: 1. Násob složky. 2. 5×3 + 4×5. 3. = 35.
linear_algebra
P(red) is 7/22.
{ "A": "15/22", "B": "7/23", "C": "8/22", "D": "7/22" }
mat_0772
multiple_choice
en
A bag holds 7 red and 15 blue marbles. What is P(red)?
[ "7 of 22.", "P = 7/22.", "Select option D." ]
math
Answer: 7/22 Steps: 1. 7 of 22. 2. P = 7/22. 3. Select option D. Answer: (D)
probability
Remainder: 4.
null
mat_0773
worked_example
en
Compute (193) mod 7.
[ "Divide 193 by 7.", "7×27 = 189.", "193 − 189 = 4." ]
math
Answer: Remainder: 4. Steps: 1. Divide 193 by 7. 2. 7×27 = 189. 3. 193 − 189 = 4.
number_theory
P(17,3) = 4080.
null
mat_0774
worked_example
en
Show the computation of P(17,3).
[ "n(n−1)(n−2).", "17×16×15.", "= 4080." ]
math
Answer: P(17,3) = 4080. Steps: 1. n(n−1)(n−2). 2. 17×16×15. 3. = 4080.
combinatorics
Rows: 65536.
null
mat_0775
worked_example
en
A proof checks all cases of 16 boolean variables. How many rows?
[ "2 choices each.", "2^16 = 65536." ]
math
Answer: Rows: 65536. Steps: 1. 2 choices each. 2. 2^16 = 65536.
proofs
Limit: 32.
null
mat_0776
worked_example
en
Evaluate the limit of (x² − 16²)/(x − 16) as x → 16.
[ "Factor: (x−16)(x+16).", "Cancel (x−16).", "Plug 16: 16+16 = 32." ]
math
Answer: Limit: 32. Steps: 1. Factor: (x−16)(x+16). 2. Cancel (x−16). 3. Plug 16: 16+16 = 32.
calculus
Trace: 37.
null
mat_0777
worked_example
en
Compute the trace of [[18,0],[0,19]].
[ "Sum diagonal.", "18 + 19.", "= 37." ]
math
Answer: Trace: 37. Steps: 1. Sum diagonal. 2. 18 + 19. 3. = 37.
linear_algebra
E = 10.
null
mat_0778
worked_example
en
Compute E of a uniform draw from {1..19}.
[ "Mean of 1..19.", "(19+1)/2.", "E = 10." ]
math
Answer: E = 10. Steps: 1. Mean of 1..19. 2. (19+1)/2. 3. E = 10.
probability
Zbytek: 6.
null
mat_0779
worked_example
cs
Spočítej (83) mod 7.
[ "Děl 83 sedmi.", "7×11 = 77.", "83 − 77 = 6." ]
math
Answer: Zbytek: 6. Steps: 1. Děl 83 sedmi. 2. 7×11 = 77. 3. 83 − 77 = 6.
number_theory
P(9,2) is 72.
{ "A": "63", "B": "81", "C": "90", "D": "72" }
mat_0780
multiple_choice
en
Compute P(9,2).
[ "9×8.", "= 72.", "Select option D." ]
math
Answer: 72 Steps: 1. 9×8. 2. = 72. 3. Select option D. Answer: (D)
combinatorics
Sum: 210.
null
mat_0781
worked_example
en
Prove by formula: find the sum 1 + 2 + ... + 20.
[ "Pair 1+20, 2+19, ...", "Use 20×21/2.", "= 210." ]
math
Answer: Sum: 210. Steps: 1. Pair 1+20, 2+19, ... 2. Use 20×21/2. 3. = 210.
proofs
Polar or spherical coordinates match round symmetry, making hard integrals easy.
null
mat_0782
concept
en
Why change coordinates?
[ "Polar or spherical coordinates match round symmetry, making hard integrals easy.", "So the answer stands: Polar or spherical coordinates match round symmetry, making hard integrals easy." ]
math
Answer: Polar or spherical coordinates match round symmetry, making hard integrals easy. Steps: 1. Polar or spherical coordinates match round symmetry, making hard integrals easy. 2. So the answer stands: Polar or spherical coordinates match round symmetry, making hard integrals easy.
calculus
The determinant is 64.
{ "A": "61", "B": "67", "C": "64", "D": "70" }
mat_0783
multiple_choice
en
Find the determinant of [[7,2],[3,10]].
[ "7×10 − 2×3.", "Det = 64.", "Select option C." ]
math
Answer: 64 Steps: 1. 7×10 − 2×3. 2. Det = 64. 3. Select option C. Answer: (C)
linear_algebra
P(red) = 17/21.
null
mat_0784
worked_example
en
A bag holds 17 red and 4 blue marbles. Show P(red).
[ "Red: 17.", "Total: 21.", "P = 17/21." ]
math
Answer: P(red) = 17/21. Steps: 1. Red: 17. 2. Total: 21. 3. P = 17/21.
probability
It tests primality fast with random bases, practical for cryptographic-size numbers.
null
mat_0785
concept
en
Why Miller-Rabin?
[ "It tests primality fast with random bases, practical for cryptographic-size numbers.", "So the answer stands: It tests primality fast with random bases, practical for cryptographic-size numbers." ]
math
Answer: It tests primality fast with random bases, practical for cryptographic-size numbers. Steps: 1. It tests primality fast with random bases, practical for cryptographic-size numbers. 2. So the answer stands: It tests primality fast with random bases, practical for cryptographic-size numbers.
number_theory
Derangement share nears 1/e, a lovely limit from inclusion-exclusion sums.
null
mat_0786
concept
en
Why derangements approximate?
[ "Derangement share nears 1/e, a lovely limit from inclusion-exclusion sums.", "So the answer stands: Derangement share nears 1/e, a lovely limit from inclusion-exclusion sums." ]
math
Answer: Derangement share nears 1/e, a lovely limit from inclusion-exclusion sums. Steps: 1. Derangement share nears 1/e, a lovely limit from inclusion-exclusion sums. 2. So the answer stands: Derangement share nears 1/e, a lovely limit from inclusion-exclusion sums.
combinatorics
The contrapositive is not-Q to not-P, and it is logically equivalent to the original implication.
null
mat_0787
concept
en
What is the contrapositive of P to Q?
[ "The contrapositive is not-Q to not-P, and it is logically equivalent to the original implication.", "So the answer stands: The contrapositive is not-Q to not-P, and it is logically equivalent to the original implication." ]
math
Answer: The contrapositive is not-Q to not-P, and it is logically equivalent to the original implication. Steps: 1. The contrapositive is not-Q to not-P, and it is logically equivalent to the original implication. 2. So the answer stands: The contrapositive is not-Q to not-P, and it is logically equivalent to the origi...
proofs
The integral is 729.
{ "A": "729", "B": "720", "C": "738", "D": "747" }
mat_0788
multiple_choice
en
Compute the integral of 3x² from 0 to 9.
[ "Antiderivative x³.", "9³ = 729.", "Select option A." ]
math
Answer: 729 Steps: 1. Antiderivative x³. 2. 9³ = 729. 3. Select option A. Answer: (A)
calculus
Báze je nezávislá množina napínající prostor, dává jednoznačné souřadnice.
null
mat_0789
concept
cs
Co je báze?
[ "Báze je nezávislá množina napínající prostor, dává jednoznačné souřadnice.", "Odpověď tedy platí: Báze je nezávislá množina napínající prostor, dává jednoznačné souřadnice." ]
math
Answer: Báze je nezávislá množina napínající prostor, dává jednoznačné souřadnice. Steps: 1. Báze je nezávislá množina napínající prostor, dává jednoznačné souřadnice. 2. Odpověď tedy platí: Báze je nezávislá množina napínající prostor, dává jednoznačné souřadnice.
linear_algebra
P = 1/21.
null
mat_0790
worked_example
en
A fair 21-sided die is rolled. Show P(one specific number).
[ "Favourable: 1.", "Possible: 21.", "P = 1/21." ]
math
Answer: P = 1/21. Steps: 1. Favourable: 1. 2. Possible: 21. 3. P = 1/21.
probability
lcm = 72.
null
mat_0791
worked_example
en
Compute lcm(18, 8) step by step.
[ "gcd(18,8) = 2.", "18×8/2.", "= 72." ]
math
Answer: lcm = 72. Steps: 1. gcd(18,8) = 2. 2. 18×8/2. 3. = 72.
number_theory
C(19,3) = 969.
null
mat_0792
worked_example
en
Show the computation of C(19,3).
[ "n(n−1)(n−2)/6.", "19×18×17/6.", "= 969." ]
math
Answer: C(19,3) = 969. Steps: 1. n(n−1)(n−2)/6. 2. 19×18×17/6. 3. = 969.
combinatorics
Součet: 55.
null
mat_0793
worked_example
cs
Dokaž vzorcem: najdi součet 1 + 2 + ... + 10.
[ "Páruj 1+10, 2+9, ...", "Použij 10×11/2.", "= 55." ]
math
Answer: Součet: 55. Steps: 1. Páruj 1+10, 2+9, ... 2. Použij 10×11/2. 3. = 55.
proofs
The limit is 18.
{ "A": "16", "B": "18", "C": "20", "D": "22" }
mat_0794
multiple_choice
en
Find the limit of (x² − 9²)/(x − 9) as x → 9.
[ "Factor (x−9)(x+9).", "Cancel, get 2×9 = 18.", "Select option B." ]
math
Answer: 18 Steps: 1. Factor (x−9)(x+9). 2. Cancel, get 2×9 = 18. 3. Select option B. Answer: (B)
calculus
Its roots are the eigenvalues, turning eigen-search into polynomial factoring.
null
mat_0795
concept
en
Why compute characteristic polynomial?
[ "Its roots are the eigenvalues, turning eigen-search into polynomial factoring.", "So the answer stands: Its roots are the eigenvalues, turning eigen-search into polynomial factoring." ]
math
Answer: Its roots are the eigenvalues, turning eigen-search into polynomial factoring. Steps: 1. Its roots are the eigenvalues, turning eigen-search into polynomial factoring. 2. So the answer stands: Its roots are the eigenvalues, turning eigen-search into polynomial factoring.
linear_algebra
The probability is 1/12.
{ "A": "1/11", "B": "1/13", "C": "1/12", "D": "2/12" }
mat_0796
multiple_choice
en
A fair 12-sided die is rolled. What is the probability of one specific number?
[ "1 face of 12.", "P = 1/12.", "Select option C." ]
math
Answer: 1/12 Steps: 1. 1 face of 12. 2. P = 1/12. 3. Select option C. Answer: (C)
probability
gcd = 32.
null
mat_0797
worked_example
en
Compute gcd(64, 96) step by step.
[ "Factor: 64=4×16, 96=6×16.", "Common: 16×gcd(4,6).", "= 16×2 = 32." ]
math
Answer: gcd = 32. Steps: 1. Factor: 64=4×16, 96=6×16. 2. Common: 16×gcd(4,6). 3. = 16×2 = 32.
number_theory
C(19,2) = 171.
null
mat_0798
worked_example
en
Show the computation of C(19,2).
[ "Formula n(n−1)/2.", "19×18/2.", "= 171." ]
math
Answer: C(19,2) = 171. Steps: 1. Formula n(n−1)/2. 2. 19×18/2. 3. = 171.
combinatorics
Half: 136, so 272 is even.
null
mat_0799
worked_example
en
Show N² + N is even for N = 16 by computing its half.
[ "16² + 16 = 272.", "272 / 2 = 136.", "Integer, so even." ]
math
Answer: Half: 136, so 272 is even. Steps: 1. 16² + 16 = 272. 2. 272 / 2 = 136. 3. Integer, so even.
proofs
f'(4) = 47.
null
mat_0800
worked_example
en
For f(x) = 4x² + 15x, compute f'(4) step by step.
[ "f'(x) = 8x + 15.", "Plug x = 4.", "8×4 + 15 = 47." ]
math
Answer: f'(4) = 47. Steps: 1. f'(x) = 8x + 15. 2. Plug x = 4. 3. 8×4 + 15 = 47.
calculus
Dot product: 131.
null
mat_0801
worked_example
en
Compute (17,16) · (3,5) step by step.
[ "Multiply components.", "17×3 + 16×5.", "= 131." ]
math
Answer: Dot product: 131. Steps: 1. Multiply components. 2. 17×3 + 16×5. 3. = 131.
linear_algebra
A prior encodes beliefs before data, and Bayes updates it into the posterior.
null
mat_0802
concept
en
What is a prior?
[ "A prior encodes beliefs before data, and Bayes updates it into the posterior.", "So the answer stands: A prior encodes beliefs before data, and Bayes updates it into the posterior." ]
math
Answer: A prior encodes beliefs before data, and Bayes updates it into the posterior. Steps: 1. A prior encodes beliefs before data, and Bayes updates it into the posterior. 2. So the answer stands: A prior encodes beliefs before data, and Bayes updates it into the posterior.
probability
The remainder is 5.
{ "A": "5", "B": "6", "C": "7", "D": "8" }
mat_0803
multiple_choice
en
Find (149) mod 9.
[ "149 ÷ 9.", "Remainder 5.", "Select option A." ]
math
Answer: 5 Steps: 1. 149 ÷ 9. 2. Remainder 5. 3. Select option A. Answer: (A)
number_theory
Opravuje dvojí započtení střídavými součty.
null
mat_0804
concept
cs
Co je princip inkluze?
[ "Opravuje dvojí započtení střídavými součty.", "Odpověď tedy platí: Opravuje dvojí započtení střídavými součty." ]
math
Answer: Opravuje dvojí započtení střídavými součty. Steps: 1. Opravuje dvojí započtení střídavými součty. 2. Odpověď tedy platí: Opravuje dvojí započtení střídavými součty.
combinatorics
Negating for-all yields exists-not, so sloppy negation flips the claim's meaning entirely.
null
mat_0805
concept
en
Why negate quantifiers carefully?
[ "Negating for-all yields exists-not, so sloppy negation flips the claim's meaning entirely.", "So the answer stands: Negating for-all yields exists-not, so sloppy negation flips the claim's meaning entirely." ]
math
Answer: Negating for-all yields exists-not, so sloppy negation flips the claim's meaning entirely. Steps: 1. Negating for-all yields exists-not, so sloppy negation flips the claim's meaning entirely. 2. So the answer stands: Negating for-all yields exists-not, so sloppy negation flips the claim's meaning entirely.
proofs
Integral: 4913.
null
mat_0806
worked_example
en
Evaluate the integral of 3x² from 0 to 17.
[ "Antiderivative: x³.", "Evaluate 0 to 17.", "17³ − 0 = 4913." ]
math
Answer: Integral: 4913. Steps: 1. Antiderivative: x³. 2. Evaluate 0 to 17. 3. 17³ − 0 = 4913.
calculus
The trace is 19.
{ "A": "17", "B": "21", "C": "23", "D": "19" }
mat_0807
multiple_choice
en
Find the trace of [[8,1],[2,11]].
[ "8 + 11.", "Trace = 19.", "Select option D." ]
math
Answer: 19 Steps: 1. 8 + 11. 2. Trace = 19. 3. Select option D. Answer: (D)
linear_algebra
P = 1/9.
null
mat_0808
worked_example
cs
Hází se férovou 9-stěnnou kostkou. Ukaž P(jedno konkrétní číslo).
[ "Příznivé: 1.", "Možné: 9.", "P = 1/9." ]
math
Answer: P = 1/9. Steps: 1. Příznivé: 1. 2. Možné: 9. 3. P = 1/9.
probability
Remainder: 1.
null
mat_0809
worked_example
en
Compute (204) mod 7.
[ "Divide 204 by 7.", "7×29 = 203.", "204 − 203 = 1." ]
math
Answer: Remainder: 1. Steps: 1. Divide 204 by 7. 2. 7×29 = 203. 3. 204 − 203 = 1.
number_theory
Více předmětů než krabic vynutí sdílení.
null
mat_0810
concept
cs
Proč Dirichletův princip?
[ "Více předmětů než krabic vynutí sdílení.", "Odpověď tedy platí: Více předmětů než krabic vynutí sdílení." ]
math
Answer: Více předmětů než krabic vynutí sdílení. Steps: 1. Více předmětů než krabic vynutí sdílení. 2. Odpověď tedy platí: Více předmětů než krabic vynutí sdílení.
combinatorics
The value is 110.
{ "A": "108", "B": "110", "C": "112", "D": "114" }
mat_0811
multiple_choice
en
Compute N² + N for N = 10.
[ "10² + 10.", "Value = 110.", "Select option B." ]
math
Answer: 110 Steps: 1. 10² + 10. 2. Value = 110. 3. Select option B. Answer: (B)
proofs
Limit: 34.
null
mat_0812
worked_example
en
Evaluate the limit of (x² − 17²)/(x − 17) as x → 17.
[ "Factor: (x−17)(x+17).", "Cancel (x−17).", "Plug 17: 17+17 = 34." ]
math
Answer: Limit: 34. Steps: 1. Factor: (x−17)(x+17). 2. Cancel (x−17). 3. Plug 17: 17+17 = 34.
calculus
The trace sums diagonal entries, equal to the eigenvalue sum and invariant under basis change.
null
mat_0813
concept
en
What is the trace?
[ "The trace sums diagonal entries, equal to the eigenvalue sum and invariant under basis change.", "So the answer stands: The trace sums diagonal entries, equal to the eigenvalue sum and invariant under basis change." ]
math
Answer: The trace sums diagonal entries, equal to the eigenvalue sum and invariant under basis change. Steps: 1. The trace sums diagonal entries, equal to the eigenvalue sum and invariant under basis change. 2. So the answer stands: The trace sums diagonal entries, equal to the eigenvalue sum and invariant under basis ...
linear_algebra
The expected value is 5.5.
{ "A": "6.5", "B": "4.5", "C": "7.5", "D": "5.5" }
mat_0814
multiple_choice
en
Find the expected value of a uniform draw from {1..10}.
[ "(10+1)/2.", "E = 5.5.", "Select option D." ]
math
Answer: 5.5 Steps: 1. (10+1)/2. 2. E = 5.5. 3. Select option D. Answer: (D)
probability
lcm = 152.
null
mat_0815
worked_example
en
Compute lcm(19, 8) step by step.
[ "gcd(19,8) = 1.", "19×8/1.", "= 152." ]
math
Answer: lcm = 152. Steps: 1. gcd(19,8) = 1. 2. 19×8/1. 3. = 152.
number_theory
Permutace řadí objekty, n různých jich má právě n!.
null
mat_0816
concept
cs
Co je permutace?
[ "Permutace řadí objekty, n různých jich má právě n!.", "Odpověď tedy platí: Permutace řadí objekty, n různých jich má právě n!." ]
math
Answer: Permutace řadí objekty, n různých jich má právě n!. Steps: 1. Permutace řadí objekty, n různých jich má právě n!. 2. Odpověď tedy platí: Permutace řadí objekty, n různých jich má právě n!.
combinatorics
The table has 1024 rows.
{ "A": "1024", "B": "1022", "C": "1026", "D": "1028" }
mat_0817
multiple_choice
en
How many rows does a truth table with 10 variables have?
[ "2^10 rows.", "Total: 1024.", "Select option A." ]
math
Answer: 1024 Steps: 1. 2^10 rows. 2. Total: 1024. 3. Select option A. Answer: (A)
proofs
Divergence measures net outflow of a field at a point, flagging sources and sinks.
null
mat_0818
concept
en
What is divergence?
[ "Divergence measures net outflow of a field at a point, flagging sources and sinks.", "So the answer stands: Divergence measures net outflow of a field at a point, flagging sources and sinks." ]
math
Answer: Divergence measures net outflow of a field at a point, flagging sources and sinks. Steps: 1. Divergence measures net outflow of a field at a point, flagging sources and sinks. 2. So the answer stands: Divergence measures net outflow of a field at a point, flagging sources and sinks.
calculus
The dot product is 53.
{ "A": "53", "B": "49", "C": "57", "D": "61" }
mat_0819
multiple_choice
en
Find the dot product (7,8) · (3,4).
[ "7×3 + 8×4.", "Product = 53.", "Select option A." ]
math
Answer: 53 Steps: 1. 7×3 + 8×4. 2. Product = 53. 3. Select option A. Answer: (A)
linear_algebra
E = 10.5.
null
mat_0820
worked_example
en
Compute E of a uniform draw from {1..20}.
[ "Mean of 1..20.", "(20+1)/2.", "E = 10.5." ]
math
Answer: E = 10.5. Steps: 1. Mean of 1..20. 2. (20+1)/2. 3. E = 10.5.
probability
RSA multiplies primes for public keys, secure because factoring stays hard.
null
mat_0821
concept
en
What is RSA?
[ "RSA multiplies primes for public keys, secure because factoring stays hard.", "So the answer stands: RSA multiplies primes for public keys, secure because factoring stays hard." ]
math
Answer: RSA multiplies primes for public keys, secure because factoring stays hard. Steps: 1. RSA multiplies primes for public keys, secure because factoring stays hard. 2. So the answer stands: RSA multiplies primes for public keys, secure because factoring stays hard.
number_theory
P(7,3) = 210.
null
mat_0822
worked_example
cs
Ukaž výpočet P(7,3).
[ "n(n−1)(n−2).", "7×6×5.", "= 210." ]
math
Answer: P(7,3) = 210. Steps: 1. n(n−1)(n−2). 2. 7×6×5. 3. = 210.
combinatorics
Polovina: 21, číslo 42 je sudé.
null
mat_0823
worked_example
cs
Ukaž, že N² + N je sudé pro N = 6, výpočtem poloviny.
[ "6² + 6 = 42.", "42 / 2 = 21.", "Celé číslo, tedy sudé." ]
math
Answer: Polovina: 21, číslo 42 je sudé. Steps: 1. 6² + 6 = 42. 2. 42 / 2 = 21. 3. Celé číslo, tedy sudé.
proofs
f'(2) = 12.
null
mat_0824
worked_example
cs
Pro f(x) = 2x² + 4x spočítej f'(2) krok za krokem.
[ "f'(x) = 4x + 4.", "Dosaď x = 2.", "4×2 + 4 = 12." ]
math
Answer: f'(2) = 12. Steps: 1. f'(x) = 4x + 4. 2. Dosaď x = 2. 3. 4×2 + 4 = 12.
calculus
The determinant is 82.
{ "A": "79", "B": "85", "C": "88", "D": "82" }
mat_0825
multiple_choice
en
Find the determinant of [[8,2],[3,11]].
[ "8×11 − 2×3.", "Det = 82.", "Select option D." ]
math
Answer: 82 Steps: 1. 8×11 − 2×3. 2. Det = 82. 3. Select option D. Answer: (D)
linear_algebra
P(red) is 8/25.
{ "A": "8/25", "B": "17/25", "C": "8/26", "D": "9/25" }
mat_0826
multiple_choice
en
A bag holds 8 red and 17 blue marbles. What is P(red)?
[ "8 of 25.", "P = 8/25.", "Select option A." ]
math
Answer: 8/25 Steps: 1. 8 of 25. 2. P = 8/25. 3. Select option A. Answer: (A)
probability
They invert exponentiation mod p, hard enough to secure key exchange protocols.
null
mat_0827
concept
en
Why discrete logs?
[ "They invert exponentiation mod p, hard enough to secure key exchange protocols.", "So the answer stands: They invert exponentiation mod p, hard enough to secure key exchange protocols." ]
math
Answer: They invert exponentiation mod p, hard enough to secure key exchange protocols. Steps: 1. They invert exponentiation mod p, hard enough to secure key exchange protocols. 2. So the answer stands: They invert exponentiation mod p, hard enough to secure key exchange protocols.
number_theory
P(18,3) = 4896.
null
mat_0828
worked_example
en
Show the computation of P(18,3).
[ "n(n−1)(n−2).", "18×17×16.", "= 4896." ]
math
Answer: P(18,3) = 4896. Steps: 1. n(n−1)(n−2). 2. 18×17×16. 3. = 4896.
combinatorics
Odpověď je svědek či počítání.
{ "A": "svědek či počítání", "B": "dlouhá jména", "C": "velké fonty", "D": "samotná naděje" }
mat_0829
multiple_choice
cs
Vyber: co dokazuje existenci?
[ "Sestroj nebo spočítej.", "Tedy: svědek či počítání.", "Vyber možnost A." ]
math
Answer: svědek či počítání Steps: 1. Sestroj nebo spočítej. 2. Tedy: svědek či počítání. 3. Vyber možnost A. Answer: (A)
proofs
f'(2) = 24.
null
mat_0830
worked_example
en
For f(x) = 2x² + 16x, compute f'(2) step by step.
[ "f'(x) = 4x + 16.", "Plug x = 2.", "4×2 + 16 = 24." ]
math
Answer: f'(2) = 24. Steps: 1. f'(x) = 4x + 16. 2. Plug x = 2. 3. 4×2 + 16 = 24.
calculus
The trace is 21.
{ "A": "21", "B": "19", "C": "23", "D": "25" }
mat_0831
multiple_choice
en
Find the trace of [[9,1],[2,12]].
[ "9 + 12.", "Trace = 21.", "Select option A." ]
math
Answer: 21 Steps: 1. 9 + 12. 2. Trace = 21. 3. Select option A. Answer: (A)
linear_algebra
The probability is 1/13.
{ "A": "1/12", "B": "1/14", "C": "2/13", "D": "1/13" }
mat_0832
multiple_choice
en
A fair 13-sided die is rolled. What is the probability of one specific number?
[ "1 face of 13.", "P = 1/13.", "Select option D." ]
math
Answer: 1/13 Steps: 1. 1 face of 13. 2. P = 1/13. 3. Select option D. Answer: (D)
probability
sigma(n) sums all divisors, multiplicative over prime powers for easy formulas.
null
mat_0833
concept
en
What is the sigma function?
[ "sigma(n) sums all divisors, multiplicative over prime powers for easy formulas.", "So the answer stands: sigma(n) sums all divisors, multiplicative over prime powers for easy formulas." ]
math
Answer: sigma(n) sums all divisors, multiplicative over prime powers for easy formulas. Steps: 1. sigma(n) sums all divisors, multiplicative over prime powers for easy formulas. 2. So the answer stands: sigma(n) sums all divisors, multiplicative over prime powers for easy formulas.
number_theory
C(20,3) = 1140.
null
mat_0834
worked_example
en
Show the computation of C(20,3).
[ "n(n−1)(n−2)/6.", "20×19×18/6.", "= 1140." ]
math
Answer: C(20,3) = 1140. Steps: 1. n(n−1)(n−2)/6. 2. 20×19×18/6. 3. = 1140.
combinatorics
A tautology is true under every assignment, like P-or-not-P, and truth tables detect it.
null
mat_0835
concept
en
What is a tautology?
[ "A tautology is true under every assignment, like P-or-not-P, and truth tables detect it.", "So the answer stands: A tautology is true under every assignment, like P-or-not-P, and truth tables detect it." ]
math
Answer: A tautology is true under every assignment, like P-or-not-P, and truth tables detect it. Steps: 1. A tautology is true under every assignment, like P-or-not-P, and truth tables detect it. 2. So the answer stands: A tautology is true under every assignment, like P-or-not-P, and truth tables detect it.
proofs
The derivative is 16.
{ "A": "16", "B": "14", "C": "18", "D": "20" }
mat_0836
multiple_choice
en
For f(x) = 3x² + 10x, find f'(1).
[ "f'(x) = 6x + 10.", "At 1: 16.", "Select option A." ]
math
Answer: 16 Steps: 1. f'(x) = 6x + 10. 2. At 1: 16. 3. Select option A. Answer: (A)
calculus
The dot product is 60.
{ "A": "56", "B": "60", "C": "64", "D": "68" }
mat_0837
multiple_choice
en
Find the dot product (8,9) · (3,4).
[ "8×3 + 9×4.", "Product = 60.", "Select option B." ]
math
Answer: 60 Steps: 1. 8×3 + 9×4. 2. Product = 60. 3. Select option B. Answer: (B)
linear_algebra
The expected value is 6.
{ "A": "6", "B": "7", "C": "5", "D": "8" }
mat_0838
multiple_choice
en
Find the expected value of a uniform draw from {1..11}.
[ "(11+1)/2.", "E = 6.", "Select option A." ]
math
Answer: 6 Steps: 1. (11+1)/2. 2. E = 6. 3. Select option A. Answer: (A)
probability
They split over coprime products, reducing all values to prime-power cases.
null
mat_0839
concept
en
Why multiplicative functions?
[ "They split over coprime products, reducing all values to prime-power cases.", "So the answer stands: They split over coprime products, reducing all values to prime-power cases." ]
math
Answer: They split over coprime products, reducing all values to prime-power cases. Steps: 1. They split over coprime products, reducing all values to prime-power cases. 2. So the answer stands: They split over coprime products, reducing all values to prime-power cases.
number_theory
C(11,3) is 165.
{ "A": "165", "B": "154", "C": "176", "D": "187" }
mat_0840
multiple_choice
en
Compute C(11,3).
[ "11×10×9/6.", "= 165.", "Select option A." ]
math
Answer: 165 Steps: 1. 11×10×9/6. 2. = 165. 3. Select option A. Answer: (A)
combinatorics
The sum is 91.
{ "A": "78", "B": "91", "C": "104", "D": "117" }
mat_0841
multiple_choice
en
What is the sum 1 + 2 + ... + 13?
[ "13×14/2.", "Sum = 91.", "Select option B." ]
math
Answer: 91 Steps: 1. 13×14/2. 2. Sum = 91. 3. Select option B. Answer: (B)
proofs
Integral: 5832.
null
mat_0842
worked_example
en
Evaluate the integral of 3x² from 0 to 18.
[ "Antiderivative: x³.", "Evaluate 0 to 18.", "18³ − 0 = 5832." ]
math
Answer: Integral: 5832. Steps: 1. Antiderivative: x³. 2. Evaluate 0 to 18. 3. 18³ − 0 = 5832.
calculus
Symmetric matrices have real eigenvalues and orthogonal eigenvectors, ideal for geometry.
null
mat_0843
concept
en
Why symmetric matrices?
[ "Symmetric matrices have real eigenvalues and orthogonal eigenvectors, ideal for geometry.", "So the answer stands: Symmetric matrices have real eigenvalues and orthogonal eigenvectors, ideal for geometry." ]
math
Answer: Symmetric matrices have real eigenvalues and orthogonal eigenvectors, ideal for geometry. Steps: 1. Symmetric matrices have real eigenvalues and orthogonal eigenvectors, ideal for geometry. 2. So the answer stands: Symmetric matrices have real eigenvalues and orthogonal eigenvectors, ideal for geometry.
linear_algebra
P(red) is 9/28.
{ "A": "19/28", "B": "9/28", "C": "9/29", "D": "10/28" }
mat_0844
multiple_choice
en
A bag holds 9 red and 19 blue marbles. What is P(red)?
[ "9 of 28.", "P = 9/28.", "Select option B." ]
math
Answer: 9/28 Steps: 1. 9 of 28. 2. P = 9/28. 3. Select option B. Answer: (B)
probability
The lcm is 66.
{ "A": "64", "B": "66", "C": "68", "D": "70" }
mat_0845
multiple_choice
en
Find lcm(11, 6).
[ "11×6/gcd.", "lcm = 66.", "Select option B." ]
math
Answer: 66 Steps: 1. 11×6/gcd. 2. lcm = 66. 3. Select option B. Answer: (B)
number_theory
C(11,2) is 55.
{ "A": "44", "B": "66", "C": "77", "D": "55" }
mat_0846
multiple_choice
en
Compute C(11,2).
[ "11×10/2.", "= 55.", "Select option D." ]
math
Answer: 55 Steps: 1. 11×10/2. 2. = 55. 3. Select option D. Answer: (D)
combinatorics
Rows: 131072.
null
mat_0847
worked_example
en
A proof checks all cases of 17 boolean variables. How many rows?
[ "2 choices each.", "2^17 = 131072." ]
math
Answer: Rows: 131072. Steps: 1. 2 choices each. 2. 2^17 = 131072.
proofs
Odpověď je l'Hôpitalovo pravidlo.
{ "A": "l'Hôpitalovo pravidlo", "B": "hádání", "C": "ignorování", "D": "mazání" }
mat_0848
multiple_choice
cs
Vyber: co řeší 0/0?
[ "Derivuj čitatel i jmenovatel.", "Tedy: l'Hôpitalovo pravidlo.", "Vyber možnost A." ]
math
Answer: l'Hôpitalovo pravidlo Steps: 1. Derivuj čitatel i jmenovatel. 2. Tedy: l'Hôpitalovo pravidlo. 3. Vyber možnost A. Answer: (A)
calculus
Positive definite matrices give positive energy for all nonzero vectors, guaranteeing minima.
null
mat_0849
concept
en
What is positive definite?
[ "Positive definite matrices give positive energy for all nonzero vectors, guaranteeing minima.", "So the answer stands: Positive definite matrices give positive energy for all nonzero vectors, guaranteeing minima." ]
math
Answer: Positive definite matrices give positive energy for all nonzero vectors, guaranteeing minima. Steps: 1. Positive definite matrices give positive energy for all nonzero vectors, guaranteeing minima. 2. So the answer stands: Positive definite matrices give positive energy for all nonzero vectors, guaranteeing min...
linear_algebra
The probability is 1/14.
{ "A": "1/14", "B": "1/13", "C": "1/15", "D": "2/14" }
mat_0850
multiple_choice
en
A fair 14-sided die is rolled. What is the probability of one specific number?
[ "1 face of 14.", "P = 1/14.", "Select option A." ]
math
Answer: 1/14 Steps: 1. 1 face of 14. 2. P = 1/14. 3. Select option A. Answer: (A)
probability