answer
string
choices
dict
id
string
kind
string
lang
string
question
string
steps
list
subject
string
text
string
topic
string
lcm = 104.
null
mat_0551
worked_example
en
Compute lcm(13, 8) step by step.
[ "gcd(13,8) = 1.", "13×8/1.", "= 104." ]
math
Answer: lcm = 104. Steps: 1. gcd(13,8) = 1. 2. 13×8/1. 3. = 104.
number_theory
Staví řádky sčítáním a ukazuje symetrie.
null
mat_0552
concept
cs
Proč Pascalův trojúhelník?
[ "Staví řádky sčítáním a ukazuje symetrie.", "Odpověď tedy platí: Staví řádky sčítáním a ukazuje symetrie." ]
math
Answer: Staví řádky sčítáním a ukazuje symetrie. Steps: 1. Staví řádky sčítáním a ukazuje symetrie. 2. Odpověď tedy platí: Staví řádky sčítáním a ukazuje symetrie.
combinatorics
Truth tables list every combination of truth values, so they verify logical equivalences mechanically.
null
mat_0553
concept
en
Why learn truth tables?
[ "Truth tables list every combination of truth values, so they verify logical equivalences mechanically.", "So the answer stands: Truth tables list every combination of truth values, so they verify logical equivalences mechanically." ]
math
Answer: Truth tables list every combination of truth values, so they verify logical equivalences mechanically. Steps: 1. Truth tables list every combination of truth values, so they verify logical equivalences mechanically. 2. So the answer stands: Truth tables list every combination of truth values, so they verify log...
proofs
They find extrema under constraints by aligning gradients, solving optimization with limits.
null
mat_0554
concept
en
Why use Lagrange multipliers?
[ "They find extrema under constraints by aligning gradients, solving optimization with limits.", "So the answer stands: They find extrema under constraints by aligning gradients, solving optimization with limits." ]
math
Answer: They find extrema under constraints by aligning gradients, solving optimization with limits. Steps: 1. They find extrema under constraints by aligning gradients, solving optimization with limits. 2. So the answer stands: They find extrema under constraints by aligning gradients, solving optimization with limits...
calculus
It solves systems via determinant ratios, elegant for theory though slow in practice.
null
mat_0555
concept
en
What is Cramer's rule?
[ "It solves systems via determinant ratios, elegant for theory though slow in practice.", "So the answer stands: It solves systems via determinant ratios, elegant for theory though slow in practice." ]
math
Answer: It solves systems via determinant ratios, elegant for theory though slow in practice. Steps: 1. It solves systems via determinant ratios, elegant for theory though slow in practice. 2. So the answer stands: It solves systems via determinant ratios, elegant for theory though slow in practice.
linear_algebra
P = 1/15.
null
mat_0556
worked_example
en
A fair 15-sided die is rolled. Show P(one specific number).
[ "Favourable: 1.", "Possible: 15.", "P = 1/15." ]
math
Answer: P = 1/15. Steps: 1. Favourable: 1. 2. Possible: 15. 3. P = 1/15.
probability
Opakované zbytky rychle zmenšují dvojici.
null
mat_0557
concept
cs
Proč Euklidův algoritmus?
[ "Opakované zbytky rychle zmenšují dvojici.", "Odpověď tedy platí: Opakované zbytky rychle zmenšují dvojici." ]
math
Answer: Opakované zbytky rychle zmenšují dvojici. Steps: 1. Opakované zbytky rychle zmenšují dvojici. 2. Odpověď tedy platí: Opakované zbytky rychle zmenšují dvojici.
number_theory
Rook placements count permutations with restrictions, via inclusion-exclusion boards.
null
mat_0558
concept
en
Why rook theory?
[ "Rook placements count permutations with restrictions, via inclusion-exclusion boards.", "So the answer stands: Rook placements count permutations with restrictions, via inclusion-exclusion boards." ]
math
Answer: Rook placements count permutations with restrictions, via inclusion-exclusion boards. Steps: 1. Rook placements count permutations with restrictions, via inclusion-exclusion boards. 2. So the answer stands: Rook placements count permutations with restrictions, via inclusion-exclusion boards.
combinatorics
Sum: 136.
null
mat_0559
worked_example
en
Prove by formula: find the sum 1 + 2 + ... + 16.
[ "Pair 1+16, 2+15, ...", "Use 16×17/2.", "= 136." ]
math
Answer: Sum: 136. Steps: 1. Pair 1+16, 2+15, ... 2. Use 16×17/2. 3. = 136.
proofs
The derivative is 10.
{ "A": "10", "B": "8", "C": "12", "D": "14" }
mat_0560
multiple_choice
en
For f(x) = 2x² + 6x, find f'(1).
[ "f'(x) = 4x + 6.", "At 1: 10.", "Select option A." ]
math
Answer: 10 Steps: 1. f'(x) = 4x + 6. 2. At 1: 10. 3. Select option A. Answer: (A)
calculus
Determinant: 154.
null
mat_0561
worked_example
en
Compute det [[12,1],[2,13]] step by step.
[ "ad − bc.", "12×13 − 1×2.", "= 154." ]
math
Answer: Determinant: 154. Steps: 1. ad − bc. 2. 12×13 − 1×2. 3. = 154.
linear_algebra
E = 3,5.
null
mat_0562
worked_example
cs
Spočítej E rovnoměrného tahu z {1..6}.
[ "Průměr 1..6.", "(6+1)/2.", "E = 3,5." ]
math
Answer: E = 3,5. Steps: 1. Průměr 1..6. 2. (6+1)/2. 3. E = 3,5.
probability
It equals the sum of its proper divisors, like 6 = 1+2+3, rare and mysterious.
null
mat_0563
concept
en
What is a perfect number?
[ "It equals the sum of its proper divisors, like 6 = 1+2+3, rare and mysterious.", "So the answer stands: It equals the sum of its proper divisors, like 6 = 1+2+3, rare and mysterious." ]
math
Answer: It equals the sum of its proper divisors, like 6 = 1+2+3, rare and mysterious. Steps: 1. It equals the sum of its proper divisors, like 6 = 1+2+3, rare and mysterious. 2. So the answer stands: It equals the sum of its proper divisors, like 6 = 1+2+3, rare and mysterious.
number_theory
C(6,3) je 20.
{ "A": "14", "B": "26", "C": "32", "D": "20" }
mat_0564
multiple_choice
cs
Vypočítej kombinační číslo C(6,3).
[ "6×5×4/6.", "= 20.", "Vyber možnost D." ]
math
Answer: 20 Steps: 1. 6×5×4/6. 2. = 20. 3. Vyber možnost D. Answer: (D)
combinatorics
Half: 78, so 156 is even.
null
mat_0565
worked_example
en
Show N² + N is even for N = 12 by computing its half.
[ "12² + 12 = 156.", "156 / 2 = 78.", "Integer, so even." ]
math
Answer: Half: 78, so 156 is even. Steps: 1. 12² + 12 = 156. 2. 156 / 2 = 78. 3. Integer, so even.
proofs
The integral is 216.
{ "A": "210", "B": "216", "C": "222", "D": "228" }
mat_0566
multiple_choice
en
Compute the integral of 3x² from 0 to 6.
[ "Antiderivative x³.", "6³ = 216.", "Select option B." ]
math
Answer: 216 Steps: 1. Antiderivative x³. 2. 6³ = 216. 3. Select option B. Answer: (B)
calculus
Trace: 27.
null
mat_0567
worked_example
en
Compute the trace of [[13,0],[0,14]].
[ "Sum diagonal.", "13 + 14.", "= 27." ]
math
Answer: Trace: 27. Steps: 1. Sum diagonal. 2. 13 + 14. 3. = 27.
linear_algebra
E = 7.5.
null
mat_0568
worked_example
en
Compute E of a uniform draw from {1..14}.
[ "Mean of 1..14.", "(14+1)/2.", "E = 7.5." ]
math
Answer: E = 7.5. Steps: 1. Mean of 1..14. 2. (14+1)/2. 3. E = 7.5.
probability
Počítá se zbytky po dělení, čísla se obtáčejí kolem hodin.
null
mat_0569
concept
cs
Co je modulární aritmetika?
[ "Počítá se zbytky po dělení, čísla se obtáčejí kolem hodin.", "Odpověď tedy platí: Počítá se zbytky po dělení, čísla se obtáčejí kolem hodin." ]
math
Answer: Počítá se zbytky po dělení, čísla se obtáčejí kolem hodin. Steps: 1. Počítá se zbytky po dělení, čísla se obtáčejí kolem hodin. 2. Odpověď tedy platí: Počítá se zbytky po dělení, čísla se obtáčejí kolem hodin.
number_theory
Odpověď je kombinační číslo.
{ "A": "kombinační číslo", "B": "n+r", "C": "n*r", "D": "n+r!" }
mat_0570
multiple_choice
cs
Vyber: co počítá podmnožiny?
[ "Pořadí vyděleno pryč.", "Tedy: kombinační číslo.", "Vyber možnost A." ]
math
Answer: kombinační číslo Steps: 1. Pořadí vyděleno pryč. 2. Tedy: kombinační číslo. 3. Vyber možnost A. Answer: (A)
combinatorics
Rows: 8192.
null
mat_0571
worked_example
en
A proof checks all cases of 13 boolean variables. How many rows?
[ "2 choices each.", "2^13 = 8192." ]
math
Answer: Rows: 8192. Steps: 1. 2 choices each. 2. 2^13 = 8192.
proofs
It relates a function to its derivatives, and solving it finds the function from its change law.
null
mat_0572
concept
en
What is a differential equation?
[ "It relates a function to its derivatives, and solving it finds the function from its change law.", "So the answer stands: It relates a function to its derivatives, and solving it finds the function from its change law." ]
math
Answer: It relates a function to its derivatives, and solving it finds the function from its change law. Steps: 1. It relates a function to its derivatives, and solving it finds the function from its change law. 2. So the answer stands: It relates a function to its derivatives, and solving it finds the function from it...
calculus
Dot product: 91.
null
mat_0573
worked_example
en
Compute (12,11) · (3,5) step by step.
[ "Multiply components.", "12×3 + 11×5.", "= 91." ]
math
Answer: Dot product: 91. Steps: 1. Multiply components. 2. 12×3 + 11×5. 3. = 91.
linear_algebra
It gives probabilities of value pairs, capturing how two variables vary together.
null
mat_0574
concept
en
What is a joint distribution?
[ "It gives probabilities of value pairs, capturing how two variables vary together.", "So the answer stands: It gives probabilities of value pairs, capturing how two variables vary together." ]
math
Answer: It gives probabilities of value pairs, capturing how two variables vary together. Steps: 1. It gives probabilities of value pairs, capturing how two variables vary together. 2. So the answer stands: It gives probabilities of value pairs, capturing how two variables vary together.
probability
Odpověď je Euklidův argument.
{ "A": "Euklidův argument", "B": "velké počítače", "C": "dlouhé seznamy", "D": "hlasitá tvrzení" }
mat_0575
multiple_choice
cs
Vyber: co nutí nová prvočísla?
[ "Součin plus jedna.", "Tedy: Euklidův argument.", "Vyber možnost A." ]
math
Answer: Euklidův argument Steps: 1. Součin plus jedna. 2. Tedy: Euklidův argument. 3. Vyber možnost A. Answer: (A)
number_theory
Rozvíjí (a+b)^n do členů s kombinačními čísly.
null
mat_0576
concept
cs
Co je binomická věta?
[ "Rozvíjí (a+b)^n do členů s kombinačními čísly.", "Odpověď tedy platí: Rozvíjí (a+b)^n do členů s kombinačními čísly." ]
math
Answer: Rozvíjí (a+b)^n do členů s kombinačními čísly. Steps: 1. Rozvíjí (a+b)^n do členů s kombinačními čísly. 2. Odpověď tedy platí: Rozvíjí (a+b)^n do členů s kombinačními čísly.
combinatorics
The sum is 55.
{ "A": "45", "B": "65", "C": "55", "D": "75" }
mat_0577
multiple_choice
en
What is the sum 1 + 2 + ... + 10?
[ "10×11/2.", "Sum = 55.", "Select option C." ]
math
Answer: 55 Steps: 1. 10×11/2. 2. Sum = 55. 3. Select option C. Answer: (C)
proofs
The limit is 12.
{ "A": "10", "B": "14", "C": "12", "D": "16" }
mat_0578
multiple_choice
en
Find the limit of (x² − 6²)/(x − 6) as x → 6.
[ "Factor (x−6)(x+6).", "Cancel, get 2×6 = 12.", "Select option C." ]
math
Answer: 12 Steps: 1. Factor (x−6)(x+6). 2. Cancel, get 2×6 = 12. 3. Select option C. Answer: (C)
calculus
Determinant: 180.
null
mat_0579
worked_example
en
Compute det [[13,1],[2,14]] step by step.
[ "ad − bc.", "13×14 − 1×2.", "= 180." ]
math
Answer: Determinant: 180. Steps: 1. ad − bc. 2. 13×14 − 1×2. 3. = 180.
linear_algebra
P(red) = 12/16.
null
mat_0580
worked_example
en
A bag holds 12 red and 4 blue marbles. Show P(red).
[ "Red: 12.", "Total: 16.", "P = 12/16." ]
math
Answer: P(red) = 12/16. Steps: 1. Red: 12. 2. Total: 16. 3. P = 12/16.
probability
Numbers 2^p-1 yield huge primes, driving record prime hunts and perfect numbers.
null
mat_0581
concept
en
Why Mersenne primes?
[ "Numbers 2^p-1 yield huge primes, driving record prime hunts and perfect numbers.", "So the answer stands: Numbers 2^p-1 yield huge primes, driving record prime hunts and perfect numbers." ]
math
Answer: Numbers 2^p-1 yield huge primes, driving record prime hunts and perfect numbers. Steps: 1. Numbers 2^p-1 yield huge primes, driving record prime hunts and perfect numbers. 2. So the answer stands: Numbers 2^p-1 yield huge primes, driving record prime hunts and perfect numbers.
number_theory
C(15,2) = 105.
null
mat_0582
worked_example
en
Show the computation of C(15,2).
[ "Formula n(n−1)/2.", "15×14/2.", "= 105." ]
math
Answer: C(15,2) = 105. Steps: 1. Formula n(n−1)/2. 2. 15×14/2. 3. = 105.
combinatorics
Modus ponens infers Q from P and P-implies-Q, and it is the basic step of deductive reasoning.
null
mat_0583
concept
en
What is modus ponens?
[ "Modus ponens infers Q from P and P-implies-Q, and it is the basic step of deductive reasoning.", "So the answer stands: Modus ponens infers Q from P and P-implies-Q, and it is the basic step of deductive reasoning." ]
math
Answer: Modus ponens infers Q from P and P-implies-Q, and it is the basic step of deductive reasoning. Steps: 1. Modus ponens infers Q from P and P-implies-Q, and it is the basic step of deductive reasoning. 2. So the answer stands: Modus ponens infers Q from P and P-implies-Q, and it is the basic step of deductive rea...
proofs
Separation splits dy/dx equations into integrable halves, solving many first-order equations.
null
mat_0584
concept
en
Why separate variables?
[ "Separation splits dy/dx equations into integrable halves, solving many first-order equations.", "So the answer stands: Separation splits dy/dx equations into integrable halves, solving many first-order equations." ]
math
Answer: Separation splits dy/dx equations into integrable halves, solving many first-order equations. Steps: 1. Separation splits dy/dx equations into integrable halves, solving many first-order equations. 2. So the answer stands: Separation splits dy/dx equations into integrable halves, solving many first-order equati...
calculus
Skalární součin: 19.
null
mat_0585
worked_example
cs
Spočítej (3,2) · (3,5) krok za krokem.
[ "Násob složky.", "3×3 + 2×5.", "= 19." ]
math
Answer: Skalární součin: 19. Steps: 1. Násob složky. 2. 3×3 + 2×5. 3. = 19.
linear_algebra
P(červená) = 4/8.
null
mat_0586
worked_example
cs
Sáček má 4 červených a 4 modré kuličky. Ukaž P(červená).
[ "Červené: 4.", "Celkem: 8.", "P = 4/8." ]
math
Answer: P(červená) = 4/8. Steps: 1. Červené: 4. 2. Celkem: 8. 3. P = 4/8.
probability
Kongruence zachovávají součty a součiny, velké úlohy zmenšují.
null
mat_0587
concept
cs
Proč kongruence?
[ "Kongruence zachovávají součty a součiny, velké úlohy zmenšují.", "Odpověď tedy platí: Kongruence zachovávají součty a součiny, velké úlohy zmenšují." ]
math
Answer: Kongruence zachovávají součty a součiny, velké úlohy zmenšují. Steps: 1. Kongruence zachovávají součty a součiny, velké úlohy zmenšují. 2. Odpověď tedy platí: Kongruence zachovávají součty a součiny, velké úlohy zmenšují.
number_theory
It extends nCr to many groups at once, dividing n! by each group factorial.
null
mat_0588
concept
en
What is the multinomial?
[ "It extends nCr to many groups at once, dividing n! by each group factorial.", "So the answer stands: It extends nCr to many groups at once, dividing n! by each group factorial." ]
math
Answer: It extends nCr to many groups at once, dividing n! by each group factorial. Steps: 1. It extends nCr to many groups at once, dividing n! by each group factorial. 2. So the answer stands: It extends nCr to many groups at once, dividing n! by each group factorial.
combinatorics
Circular proofs assume the conclusion, so they prove nothing even when every step looks valid.
null
mat_0589
concept
en
Why avoid circular proofs?
[ "Circular proofs assume the conclusion, so they prove nothing even when every step looks valid.", "So the answer stands: Circular proofs assume the conclusion, so they prove nothing even when every step looks valid." ]
math
Answer: Circular proofs assume the conclusion, so they prove nothing even when every step looks valid. Steps: 1. Circular proofs assume the conclusion, so they prove nothing even when every step looks valid. 2. So the answer stands: Circular proofs assume the conclusion, so they prove nothing even when every step looks...
proofs
Limit: 26.
null
mat_0590
worked_example
en
Evaluate the limit of (x² − 13²)/(x − 13) as x → 13.
[ "Factor: (x−13)(x+13).", "Cancel (x−13).", "Plug 13: 13+13 = 26." ]
math
Answer: Limit: 26. Steps: 1. Factor: (x−13)(x+13). 2. Cancel (x−13). 3. Plug 13: 13+13 = 26.
calculus
Linear maps preserve structure simply, modelling rotations, scalings, and projections exactly.
null
mat_0591
concept
en
Why study linear maps?
[ "Linear maps preserve structure simply, modelling rotations, scalings, and projections exactly.", "So the answer stands: Linear maps preserve structure simply, modelling rotations, scalings, and projections exactly." ]
math
Answer: Linear maps preserve structure simply, modelling rotations, scalings, and projections exactly. Steps: 1. Linear maps preserve structure simply, modelling rotations, scalings, and projections exactly. 2. So the answer stands: Linear maps preserve structure simply, modelling rotations, scalings, and projections e...
linear_algebra
The probability is 1/10.
{ "A": "1/10", "B": "1/9", "C": "1/11", "D": "2/10" }
mat_0592
multiple_choice
en
A fair 10-sided die is rolled. What is the probability of one specific number?
[ "1 face of 10.", "P = 1/10.", "Select option A." ]
math
Answer: 1/10 Steps: 1. 1 face of 10. 2. P = 1/10. 3. Select option A. Answer: (A)
probability
The lcm is 24.
{ "A": "22", "B": "26", "C": "24", "D": "28" }
mat_0593
multiple_choice
en
Find lcm(8, 6).
[ "8×6/gcd.", "lcm = 24.", "Select option C." ]
math
Answer: 24 Steps: 1. 8×6/gcd. 2. lcm = 24. 3. Select option C. Answer: (C)
number_theory
P(14,3) = 2184.
null
mat_0594
worked_example
en
Show the computation of P(14,3).
[ "n(n−1)(n−2).", "14×13×12.", "= 2184." ]
math
Answer: P(14,3) = 2184. Steps: 1. n(n−1)(n−2). 2. 14×13×12. 3. = 2184.
combinatorics
Hodnota je 12.
{ "A": "10", "B": "14", "C": "12", "D": "16" }
mat_0595
multiple_choice
cs
Vypočítej N² + N pro N = 3.
[ "3² + 3.", "Hodnota = 12.", "Vyber možnost C." ]
math
Answer: 12 Steps: 1. 3² + 3. 2. Hodnota = 12. 3. Vyber možnost C. Answer: (C)
proofs
f'(4) = 44.
null
mat_0596
worked_example
en
For f(x) = 4x² + 12x, compute f'(4) step by step.
[ "f'(x) = 8x + 12.", "Plug x = 4.", "8×4 + 12 = 44." ]
math
Answer: f'(4) = 44. Steps: 1. f'(x) = 8x + 12. 2. Plug x = 4. 3. 8×4 + 12 = 44.
calculus
The dot product is 39.
{ "A": "35", "B": "43", "C": "39", "D": "47" }
mat_0597
multiple_choice
en
Find the dot product (5,6) · (3,4).
[ "5×3 + 6×4.", "Product = 39.", "Select option C." ]
math
Answer: 39 Steps: 1. 5×3 + 6×4. 2. Product = 39. 3. Select option C. Answer: (C)
linear_algebra
P = 1/8.
null
mat_0598
worked_example
cs
Hází se férovou 8-stěnnou kostkou. Ukaž P(jedno konkrétní číslo).
[ "Příznivé: 1.", "Možné: 8.", "P = 1/8." ]
math
Answer: P = 1/8. Steps: 1. Příznivé: 1. 2. Možné: 8. 3. P = 1/8.
probability
gcd = 22.
null
mat_0599
worked_example
en
Compute gcd(44, 66) step by step.
[ "Factor: 44=4×11, 66=6×11.", "Common: 11×gcd(4,6).", "= 11×2 = 22." ]
math
Answer: gcd = 22. Steps: 1. Factor: 44=4×11, 66=6×11. 2. Common: 11×gcd(4,6). 3. = 11×2 = 22.
number_theory
It builds labelled structures from components, exponentiating their generating series.
null
mat_0600
concept
en
Why exponential formula?
[ "It builds labelled structures from components, exponentiating their generating series.", "So the answer stands: It builds labelled structures from components, exponentiating their generating series." ]
math
Answer: It builds labelled structures from components, exponentiating their generating series. Steps: 1. It builds labelled structures from components, exponentiating their generating series. 2. So the answer stands: It builds labelled structures from components, exponentiating their generating series.
combinatorics
Strong induction assumes all earlier cases to prove the next, which suits claims needing many predecessors.
null
mat_0601
concept
en
What is strong induction?
[ "Strong induction assumes all earlier cases to prove the next, which suits claims needing many predecessors.", "So the answer stands: Strong induction assumes all earlier cases to prove the next, which suits claims needing many predecessors." ]
math
Answer: Strong induction assumes all earlier cases to prove the next, which suits claims needing many predecessors. Steps: 1. Strong induction assumes all earlier cases to prove the next, which suits claims needing many predecessors. 2. So the answer stands: Strong induction assumes all earlier cases to prove the next,...
proofs
The answer is Ratio test.
{ "A": "Coin toss", "B": "Mood ring", "C": "Dice roll", "D": "Ratio test" }
mat_0602
multiple_choice
en
Choose: what tests series?
[ "Below one converges.", "So: Ratio test.", "Select option D." ]
math
Answer: Ratio test Steps: 1. Below one converges. 2. So: Ratio test. 3. Select option D. Answer: (D)
calculus
Trace: 29.
null
mat_0603
worked_example
en
Compute the trace of [[14,0],[0,15]].
[ "Sum diagonal.", "14 + 15.", "= 29." ]
math
Answer: Trace: 29. Steps: 1. Sum diagonal. 2. 14 + 15. 3. = 29.
linear_algebra
Summing out variables isolates one distribution, focusing analysis where needed.
null
mat_0604
concept
en
Why marginalize?
[ "Summing out variables isolates one distribution, focusing analysis where needed.", "So the answer stands: Summing out variables isolates one distribution, focusing analysis where needed." ]
math
Answer: Summing out variables isolates one distribution, focusing analysis where needed. Steps: 1. Summing out variables isolates one distribution, focusing analysis where needed. 2. So the answer stands: Summing out variables isolates one distribution, focusing analysis where needed.
probability
The answer is Totient phi.
{ "A": "Lucky guess", "B": "Coin toss", "C": "Dice roll", "D": "Totient phi" }
mat_0605
multiple_choice
en
Choose: what counts coprimes?
[ "Below n, coprime.", "So: Totient phi.", "Select option D." ]
math
Answer: Totient phi Steps: 1. Below n, coprime. 2. So: Totient phi. 3. Select option D. Answer: (D)
number_theory
It counts orbits under symmetry by averaging fixed points over the group.
null
mat_0606
concept
en
What is Burnside's lemma?
[ "It counts orbits under symmetry by averaging fixed points over the group.", "So the answer stands: It counts orbits under symmetry by averaging fixed points over the group." ]
math
Answer: It counts orbits under symmetry by averaging fixed points over the group. Steps: 1. It counts orbits under symmetry by averaging fixed points over the group. 2. So the answer stands: It counts orbits under symmetry by averaging fixed points over the group.
combinatorics
Divisibility proofs reveal why digit tricks work, grounding mental arithmetic in modular structure.
null
mat_0607
concept
en
Why prove divisibility rules?
[ "Divisibility proofs reveal why digit tricks work, grounding mental arithmetic in modular structure.", "So the answer stands: Divisibility proofs reveal why digit tricks work, grounding mental arithmetic in modular structure." ]
math
Answer: Divisibility proofs reveal why digit tricks work, grounding mental arithmetic in modular structure. Steps: 1. Divisibility proofs reveal why digit tricks work, grounding mental arithmetic in modular structure. 2. So the answer stands: Divisibility proofs reveal why digit tricks work, grounding mental arithmetic...
proofs
Integral: 2744.
null
mat_0608
worked_example
en
Evaluate the integral of 3x² from 0 to 14.
[ "Antiderivative: x³.", "Evaluate 0 to 14.", "14³ − 0 = 2744." ]
math
Answer: Integral: 2744. Steps: 1. Antiderivative: x³. 2. Evaluate 0 to 14. 3. 14³ − 0 = 2744.
calculus
Dot product: 99.
null
mat_0609
worked_example
en
Compute (13,12) · (3,5) step by step.
[ "Multiply components.", "13×3 + 12×5.", "= 99." ]
math
Answer: Dot product: 99. Steps: 1. Multiply components. 2. 13×3 + 12×5. 3. = 99.
linear_algebra
P = 1/16.
null
mat_0610
worked_example
en
A fair 16-sided die is rolled. Show P(one specific number).
[ "Favourable: 1.", "Possible: 16.", "P = 1/16." ]
math
Answer: P = 1/16. Steps: 1. Favourable: 1. 2. Possible: 16. 3. P = 1/16.
probability
Remainder: 2.
null
mat_0611
worked_example
en
Compute (149) mod 7.
[ "Divide 149 by 7.", "7×21 = 147.", "149 − 147 = 2." ]
math
Answer: Remainder: 2. Steps: 1. Divide 149 by 7. 2. 7×21 = 147. 3. 149 − 147 = 2.
number_theory
C(7,3) = 35.
null
mat_0612
worked_example
cs
Ukaž výpočet C(7,3).
[ "n(n−1)(n−2)/6.", "7×6×5/6.", "= 35." ]
math
Answer: C(7,3) = 35. Steps: 1. n(n−1)(n−2)/6. 2. 7×6×5/6. 3. = 35.
combinatorics
If more items than boxes exist, some box holds two, and this counting fact proves surprising claims.
null
mat_0613
concept
en
What is the pigeonhole principle?
[ "If more items than boxes exist, some box holds two, and this counting fact proves surprising claims.", "So the answer stands: If more items than boxes exist, some box holds two, and this counting fact proves surprising claims." ]
math
Answer: If more items than boxes exist, some box holds two, and this counting fact proves surprising claims. Steps: 1. If more items than boxes exist, some box holds two, and this counting fact proves surprising claims. 2. So the answer stands: If more items than boxes exist, some box holds two, and this counting fact ...
proofs
Derivace je 11.
{ "A": "9", "B": "11", "C": "13", "D": "15" }
mat_0614
multiple_choice
cs
Pro f(x) = 2x² + 3x vypočítej f'(2).
[ "f'(x) = 4x + 3.", "V 2: 11.", "Vyber možnost B." ]
math
Answer: 11 Steps: 1. f'(x) = 4x + 3. 2. V 2: 11. 3. Vyber možnost B. Answer: (B)
calculus
The kernel is the null space of a map, capturing exactly what information is lost.
null
mat_0615
concept
en
What is the kernel?
[ "The kernel is the null space of a map, capturing exactly what information is lost.", "So the answer stands: The kernel is the null space of a map, capturing exactly what information is lost." ]
math
Answer: The kernel is the null space of a map, capturing exactly what information is lost. Steps: 1. The kernel is the null space of a map, capturing exactly what information is lost. 2. So the answer stands: The kernel is the null space of a map, capturing exactly what information is lost.
linear_algebra
Výběrové průměry se blíží střední hodnotě s rostoucím počtem pokusů.
null
mat_0616
concept
cs
Co je zákon velkých čísel?
[ "Výběrové průměry se blíží střední hodnotě s rostoucím počtem pokusů.", "Odpověď tedy platí: Výběrové průměry se blíží střední hodnotě s rostoucím počtem pokusů." ]
math
Answer: Výběrové průměry se blíží střední hodnotě s rostoucím počtem pokusů. Steps: 1. Výběrové průměry se blíží střední hodnotě s rostoucím počtem pokusů. 2. Odpověď tedy platí: Výběrové průměry se blíží střední hodnotě s rostoucím počtem pokusů.
probability
lcm = 56.
null
mat_0617
worked_example
en
Compute lcm(14, 8) step by step.
[ "gcd(14,8) = 2.", "14×8/2.", "= 56." ]
math
Answer: lcm = 56. Steps: 1. gcd(14,8) = 2. 2. 14×8/2. 3. = 56.
number_theory
The answer is Binomial theorem.
{ "A": "Wild guess", "B": "Long division", "C": "Blind hope", "D": "Binomial theorem" }
mat_0618
multiple_choice
en
Choose: what expands (a+b)^n?
[ "nCr-weighted terms.", "So: Binomial theorem.", "Select option D." ]
math
Answer: Binomial theorem Steps: 1. nCr-weighted terms. 2. So: Binomial theorem. 3. Select option D. Answer: (D)
combinatorics
Sum: 153.
null
mat_0619
worked_example
en
Prove by formula: find the sum 1 + 2 + ... + 17.
[ "Pair 1+17, 2+16, ...", "Use 17×18/2.", "= 153." ]
math
Answer: Sum: 153. Steps: 1. Pair 1+17, 2+16, ... 2. Use 17×18/2. 3. = 153.
proofs
Limit: 28.
null
mat_0620
worked_example
en
Evaluate the limit of (x² − 14²)/(x − 14) as x → 14.
[ "Factor: (x−14)(x+14).", "Cancel (x−14).", "Plug 14: 14+14 = 28." ]
math
Answer: Limit: 28. Steps: 1. Factor: (x−14)(x+14). 2. Cancel (x−14). 3. Plug 14: 14+14 = 28.
calculus
Determinant: 18.
null
mat_0621
worked_example
cs
Spočítej det [[4,1],[2,5]] krok za krokem.
[ "ad − bc.", "4×5 − 1×2.", "= 18." ]
math
Answer: Determinant: 18. Steps: 1. ad − bc. 2. 4×5 − 1×2. 3. = 18.
linear_algebra
The expected value is 4.5.
{ "A": "5.5", "B": "4.5", "C": "3.5", "D": "6.5" }
mat_0622
multiple_choice
en
Find the expected value of a uniform draw from {1..8}.
[ "(8+1)/2.", "E = 4.5.", "Select option B." ]
math
Answer: 4.5 Steps: 1. (8+1)/2. 2. E = 4.5. 3. Select option B. Answer: (B)
probability
gcd = 24.
null
mat_0623
worked_example
en
Compute gcd(48, 72) step by step.
[ "Factor: 48=4×12, 72=6×12.", "Common: 12×gcd(4,6).", "= 12×2 = 24." ]
math
Answer: gcd = 24. Steps: 1. Factor: 48=4×12, 72=6×12. 2. Common: 12×gcd(4,6). 3. = 12×2 = 24.
number_theory
C(16,3) = 560.
null
mat_0624
worked_example
en
Show the computation of C(16,3).
[ "n(n−1)(n−2)/6.", "16×15×14/6.", "= 560." ]
math
Answer: C(16,3) = 560. Steps: 1. n(n−1)(n−2)/6. 2. 16×15×14/6. 3. = 560.
combinatorics
Half: 91, so 182 is even.
null
mat_0625
worked_example
en
Show N² + N is even for N = 13 by computing its half.
[ "13² + 13 = 182.", "182 / 2 = 91.", "Integer, so even." ]
math
Answer: Half: 91, so 182 is even. Steps: 1. 13² + 13 = 182. 2. 182 / 2 = 91. 3. Integer, so even.
proofs
Integrál je 27.
{ "A": "24", "B": "30", "C": "27", "D": "33" }
mat_0626
multiple_choice
cs
Vypočítej integrál 3x² od 0 do 3.
[ "Primitivní x³.", "3³ = 27.", "Vyber možnost C." ]
math
Answer: 27 Steps: 1. Primitivní x³. 2. 3³ = 27. 3. Vyber možnost C. Answer: (C)
calculus
The answer is A basis.
{ "A": "A guess", "B": "A hope", "C": "A dream", "D": "A basis" }
mat_0627
multiple_choice
en
Choose: what gives coordinates?
[ "Independent spanning set.", "So: A basis.", "Select option D." ]
math
Answer: A basis Steps: 1. Independent spanning set. 2. So: A basis. 3. Select option D. Answer: (D)
linear_algebra
E = 4.
null
mat_0628
worked_example
cs
Spočítej E rovnoměrného tahu z {1..7}.
[ "Průměr 1..7.", "(7+1)/2.", "E = 4." ]
math
Answer: E = 4. Steps: 1. Průměr 1..7. 2. (7+1)/2. 3. E = 4.
probability
Pro prvočíslo p je a^(p-1) rovno 1 mod p.
null
mat_0629
concept
cs
Co je malá Fermatova věta?
[ "Pro prvočíslo p je a^(p-1) rovno 1 mod p.", "Odpověď tedy platí: Pro prvočíslo p je a^(p-1) rovno 1 mod p." ]
math
Answer: Pro prvočíslo p je a^(p-1) rovno 1 mod p. Steps: 1. Pro prvočíslo p je a^(p-1) rovno 1 mod p. 2. Odpověď tedy platí: Pro prvočíslo p je a^(p-1) rovno 1 mod p.
number_theory
It counts colorings up to symmetry via cycle index, generalizing Burnside elegantly.
null
mat_0630
concept
en
Why Pólya counting?
[ "It counts colorings up to symmetry via cycle index, generalizing Burnside elegantly.", "So the answer stands: It counts colorings up to symmetry via cycle index, generalizing Burnside elegantly." ]
math
Answer: It counts colorings up to symmetry via cycle index, generalizing Burnside elegantly. Steps: 1. It counts colorings up to symmetry via cycle index, generalizing Burnside elegantly. 2. So the answer stands: It counts colorings up to symmetry via cycle index, generalizing Burnside elegantly.
combinatorics
Rows: 16384.
null
mat_0631
worked_example
en
A proof checks all cases of 14 boolean variables. How many rows?
[ "2 choices each.", "2^14 = 16384." ]
math
Answer: Rows: 16384. Steps: 1. 2 choices each. 2. 2^14 = 16384.
proofs
The answer is Mean value theorem.
{ "A": "Mean value theorem", "B": "Lucky guess", "C": "Long proof", "D": "Big book" }
mat_0632
multiple_choice
en
Choose: what guarantees matched rates?
[ "Some point matches.", "So: Mean value theorem.", "Select option A." ]
math
Answer: Mean value theorem Steps: 1. Some point matches. 2. So: Mean value theorem. 3. Select option A. Answer: (A)
calculus
Determinant: 208.
null
mat_0633
worked_example
en
Compute det [[14,1],[2,15]] step by step.
[ "ad − bc.", "14×15 − 1×2.", "= 208." ]
math
Answer: Determinant: 208. Steps: 1. ad − bc. 2. 14×15 − 1×2. 3. = 208.
linear_algebra
E = 8.
null
mat_0634
worked_example
en
Compute E of a uniform draw from {1..15}.
[ "Mean of 1..15.", "(15+1)/2.", "E = 8." ]
math
Answer: E = 8. Steps: 1. Mean of 1..15. 2. (15+1)/2. 3. E = 8.
probability
The answer is Riemann zeta.
{ "A": "Riemann zeta", "B": "Wild series", "C": "Blind sum", "D": "Vague total" }
mat_0635
multiple_choice
en
Choose: what sums 1/n^s?
[ "Zeros rule primes.", "So: Riemann zeta.", "Select option A." ]
math
Answer: Riemann zeta Steps: 1. Zeros rule primes. 2. So: Riemann zeta. 3. Select option A. Answer: (A)
number_theory
Rows and columns each permute symbols, the combinatorics behind sudoku puzzles.
null
mat_0636
concept
en
What is a Latin square?
[ "Rows and columns each permute symbols, the combinatorics behind sudoku puzzles.", "So the answer stands: Rows and columns each permute symbols, the combinatorics behind sudoku puzzles." ]
math
Answer: Rows and columns each permute symbols, the combinatorics behind sudoku puzzles. Steps: 1. Rows and columns each permute symbols, the combinatorics behind sudoku puzzles. 2. So the answer stands: Rows and columns each permute symbols, the combinatorics behind sudoku puzzles.
combinatorics
Kruhový důkaz předpokládá závěr, a nedokazuje tedy nic.
null
mat_0637
concept
cs
Proč se vyhnout kruhovým důkazům?
[ "Kruhový důkaz předpokládá závěr, a nedokazuje tedy nic.", "Odpověď tedy platí: Kruhový důkaz předpokládá závěr, a nedokazuje tedy nic." ]
math
Answer: Kruhový důkaz předpokládá závěr, a nedokazuje tedy nic. Steps: 1. Kruhový důkaz předpokládá závěr, a nedokazuje tedy nic. 2. Odpověď tedy platí: Kruhový důkaz předpokládá závěr, a nedokazuje tedy nic.
proofs
f'(2) = 21.
null
mat_0638
worked_example
en
For f(x) = 2x² + 13x, compute f'(2) step by step.
[ "f'(x) = 4x + 13.", "Plug x = 2.", "4×2 + 13 = 21." ]
math
Answer: f'(2) = 21. Steps: 1. f'(x) = 4x + 13. 2. Plug x = 2. 3. 4×2 + 13 = 21.
calculus
Trace: 31.
null
mat_0639
worked_example
en
Compute the trace of [[15,0],[0,16]].
[ "Sum diagonal.", "15 + 16.", "= 31." ]
math
Answer: Trace: 31. Steps: 1. Sum diagonal. 2. 15 + 16. 3. = 31.
linear_algebra
P(red) = 13/17.
null
mat_0640
worked_example
en
A bag holds 13 red and 4 blue marbles. Show P(red).
[ "Red: 13.", "Total: 17.", "P = 13/17." ]
math
Answer: P(red) = 13/17. Steps: 1. Red: 13. 2. Total: 17. 3. P = 13/17.
probability
Remainder: 6.
null
mat_0641
worked_example
en
Compute (160) mod 7.
[ "Divide 160 by 7.", "7×22 = 154.", "160 − 154 = 6." ]
math
Answer: Remainder: 6. Steps: 1. Divide 160 by 7. 2. 7×22 = 154. 3. 160 − 154 = 6.
number_theory
C(7,2) = 21.
null
mat_0642
worked_example
cs
Ukaž výpočet C(7,2).
[ "Vzorec n(n−1)/2.", "7×6/2.", "= 21." ]
math
Answer: C(7,2) = 21. Steps: 1. Vzorec n(n−1)/2. 2. 7×6/2. 3. = 21.
combinatorics
The value is 72.
{ "A": "70", "B": "74", "C": "76", "D": "72" }
mat_0643
multiple_choice
en
Compute N² + N for N = 8.
[ "8² + 8.", "Value = 72.", "Select option D." ]
math
Answer: 72 Steps: 1. 8² + 8. 2. Value = 72. 3. Select option D. Answer: (D)
proofs
Integrál: 125.
null
mat_0644
worked_example
cs
Vyčísli integrál 3x² od 0 do 5.
[ "Primitivní: x³.", "Vyčísli 0 až 5.", "5³ − 0 = 125." ]
math
Answer: Integrál: 125. Steps: 1. Primitivní: x³. 2. Vyčísli 0 až 5. 3. 5³ − 0 = 125.
calculus
Dot product: 107.
null
mat_0645
worked_example
en
Compute (14,13) · (3,5) step by step.
[ "Multiply components.", "14×3 + 13×5.", "= 107." ]
math
Answer: Dot product: 107. Steps: 1. Multiply components. 2. 14×3 + 13×5. 3. = 107.
linear_algebra
P = 1/17.
null
mat_0646
worked_example
en
A fair 17-sided die is rolled. Show P(one specific number).
[ "Favourable: 1.", "Possible: 17.", "P = 1/17." ]
math
Answer: P = 1/17. Steps: 1. Favourable: 1. 2. Possible: 17. 3. P = 1/17.
probability
The gcd is 21.
{ "A": "18", "B": "21", "C": "24", "D": "27" }
mat_0647
multiple_choice
en
Find gcd(42, 63).
[ "Factor 3 out twice.", "gcd = 21.", "Select option B." ]
math
Answer: 21 Steps: 1. Factor 3 out twice. 2. gcd = 21. 3. Select option B. Answer: (B)
number_theory
C(16,2) = 120.
null
mat_0648
worked_example
en
Show the computation of C(16,2).
[ "Formula n(n−1)/2.", "16×15/2.", "= 120." ]
math
Answer: C(16,2) = 120. Steps: 1. Formula n(n−1)/2. 2. 16×15/2. 3. = 120.
combinatorics
The table has 256 rows.
{ "A": "254", "B": "258", "C": "256", "D": "260" }
mat_0649
multiple_choice
en
How many rows does a truth table with 8 variables have?
[ "2^8 rows.", "Total: 256.", "Select option C." ]
math
Answer: 256 Steps: 1. 2^8 rows. 2. Total: 256. 3. Select option C. Answer: (C)
proofs
It steps along tangent slopes to approximate solutions numerically when formulas fail.
null
mat_0650
concept
en
What is Euler's method?
[ "It steps along tangent slopes to approximate solutions numerically when formulas fail.", "So the answer stands: It steps along tangent slopes to approximate solutions numerically when formulas fail." ]
math
Answer: It steps along tangent slopes to approximate solutions numerically when formulas fail. Steps: 1. It steps along tangent slopes to approximate solutions numerically when formulas fail. 2. So the answer stands: It steps along tangent slopes to approximate solutions numerically when formulas fail.
calculus