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5

25

votes

4

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2k

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Nested radicals of 1000 square roots

algebra-precalculus nested-radicals

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2

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When is a Sudoku like table solvable

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1

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265

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Prove that all light bulbs can't light off

combinatorics

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1

7

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1

answer

211

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Evaluting sum $\sum \limits_{n=0}^\infty\frac{n^k}{n!}$

sequences-and-series closed-form

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1

6

votes

4

answers

206

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Solve equation $\frac{1}{x}+\frac{1}{y}=\frac{2}{101}$ in naturals

algebra-precalculus elementary-number-theory

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2

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130

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Using basis $e=[x^3,x^2,x,1]$ instead of $e=[1,x,x^2,x^3]$

linear-algebra matrices reference-request vector-spaces hamel-basis

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3

votes

2

answers

337

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Proving $a\mid b^2,\,b^2\mid a^3,\,a^3\mid b^4,\ldots\implies a=b$ - why is my approach incorrect

number-theory divisibility

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2

3

votes

1

answer

202

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Cyclic quadrilateral geometry

geometry quadrilateral

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3

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3

answers

57

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Given a continuous mapping $f$ find $\lim_{n\to\infty}\int_0^1 nf(x)e^{-nx}$

calculus real-analysis continuity

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1

3

votes

1

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150

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combinatorics contest-math

Feb 4 '17 at 11:16 Dylan 6,908

1

3

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1

answer

90

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Prove $fgh$ has more then $\deg f$ different zeroes

polynomials

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2

3

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0

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160

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Biggest number divisible by $99$

algebra-precalculus elementary-number-theory proof-verification contest-math

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3

votes

1

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2k

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Two circles touch internally

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3

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1

answer

58

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Biggest common divisor

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2

votes

1

answer

1k

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Minimum number of knights so that every cell is attacked

combinatorics

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2

votes

2

answers

125

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Proving $x>\sin(x)$ without calculus for $x>0$

algebra-precalculus trigonometry inequality contest-math

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1

2

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1

answer

284

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Multivariable limit one-sided path

multivariable-calculus

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2

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1

answer

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Finding the interval after substitution

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Biggest number of creatures in forest

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soft-question self-learning

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Are given groups isomorphic

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Finding $(x,y)$ closest to $N$ points

optimization algorithms

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1

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1

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33

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Find the matrix of linear map $L^n$ with respect to basis $e$

linear-algebra matrices linear-transformations

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Elementary solution to $4^x-25^y=39$ in natural numbers

algebra-precalculus elementary-number-theory

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algebra-precalculus contest-math

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1

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arithmetic decimal-expansion

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40 Questions

Nested radicals of 1000 square roots

When is a Sudoku like table solvable

Prove that all light bulbs can't light off

Evaluting sum $\sum \limits_{n=0}^\infty\frac{n^k}{n!}$

Solve equation $\frac{1}{x}+\frac{1}{y}=\frac{2}{101}$ in naturals

Chess rook problem

Using basis $e=[x^3,x^2,x,1]$ instead of $e=[1,x,x^2,x^3]$

Why is infinite Integration by Parts valid?

Proving $a\mid b^2,\,b^2\mid a^3,\,a^3\mid b^4,\ldots\implies a=b$ - why is my approach incorrect

Cyclic quadrilateral geometry

Given a continuous mapping $f$ find $\lim_{n\to\infty}\int_0^1 nf(x)e^{-nx}$

How many sets $(A_1,A_2,\cdots, A_k)$ which are subsets of $\{1,2,\cdots ,n\}$

Prove $fgh$ has more then $\deg f$ different zeroes

Biggest number divisible by $99$

Two circles touch internally

Biggest common divisor

Intuition behind the formula for number of graphs with $n-3$ bridges

Minimum number of knights so that every cell is attacked

Proving $x>\sin(x)$ without calculus for $x>0$

Multivariable limit one-sided path

Lerch transcendent: $\text{LerchPhi}^{(0,1,0)}\left(\frac{1}{2}, 0, 2\right)$

Finding the interval after substitution

Biggest number of creatures in forest

Material for advanced highschooler

Are given groups isomorphic

Finding $(x,y)$ closest to $N$ points

Find the matrix of linear map $L^n$ with respect to basis $e$

Elementary solution to $4^x-25^y=39$ in natural numbers

Compare $4^x+1$ and $2^x+3^x$ for non-negative real $x$

Multiplying numbers splitting the number into 4 digit numbers