Question

Simple arithmetic word problem whose solution I don't understand

score 44 · Answer 1 · 2026-04-13 10:05:10

44

Views

Simple arithmetic word problem whose solution I don't understand

Published on 13 Apr 2026 - 10:05

score 2.6k · Answer 2 · 2026-04-16 02:38:03

2.6k

Views

Prove some member of the sequence $7, 77, 777, 7777, \dots$ is divisible by $2019$.

Published on 16 Apr 2026 - 2:38

score 56 · Answer 3 · 2026-04-15 16:40:04

56

Views

For every $x\in[\frac{3}{2}, 5]$ prove that: $(\sqrt{2x-3}+\sqrt{15-3x}+2\sqrt{x+1})^2<71.25$

Published on 15 Apr 2026 - 16:40

score 51 · Answer 4 · 2026-04-15 21:50:19

51

Views

Permute the entries of each column so that the row sums have absolute value $\le 2$.

Published on 15 Apr 2026 - 21:50

score 74 · Answer 5 · 2026-04-17 06:50:20

74

Views

If $g(x)=\frac{P(x)}{x^2-4}$, $\lim_{x\rightarrow\infty}g(x)=5$, and $\lim_{x\rightarrow2}g(x)=\frac{9}{4}$, find P(x) (Sweden 1950)

Published on 17 Apr 2026 - 6:50

score 124 · Answer 6 · 2026-04-15 06:39:14

124

Views

The rays $PX$ and $PY$ cut off arc $AB$ and $CD$ of a circle with radius $4$ .

Published on 15 Apr 2026 - 6:39

score 261 · Answer 7 · 2026-04-15 17:26:55

261

Views

Question on tiling of a $2n\times 2n$ square

Published on 15 Apr 2026 - 17:26

score 235 · Answer 8 · 2026-04-15 07:29:16

235

Views

Find all values of a for which the following system has a solution, no solution and infinitely many solution.

Published on 15 Apr 2026 - 7:29

score 308 · Answer 9 · 2026-04-10 13:53:39

308

Views

Tricks for questions involving finding integer solutions for a fraction which contains variables

Published on 10 Apr 2026 - 13:53

score 263 · Answer 10 · 2026-04-13 17:38:23

263

Views

General substitution method for solving first order recurrence relations with non-linear coefficients

Published on 13 Apr 2026 - 17:38

score 344 · Answer 11 · 2026-04-14 23:49:56

344

Views

How many times would you have to draw from a deck before there's at least a 90% chance you've drawn the Ace of Spades 5 times (with replacement)

Published on 14 Apr 2026 - 23:49

score 116 · Answer 12 · 2026-04-17 15:39:29

116

Views

If $z_1, z_2$ complex numbers and $u\in(0, \frac{π}{2})$ Prove that: $\frac{|z_1|^2}{\cos^2u}+\frac{|z_2|^2}{\sin^2u}\ge|z_1|^2+|z_2|^2+2Re(z_1z_2)$

Published on 17 Apr 2026 - 15:39

score 290 · Answer 13 · 2026-04-16 08:36:55

290

Views

Prove that $F(x,y)=(x-4y,2x+3y)$ is bijective

Published on 16 Apr 2026 - 8:36

score 327 · Answer 14 · 2026-04-14 09:19:02

327

Views

Alphabetical arrangement of 5 letters - MUSIC

Published on 14 Apr 2026 - 9:19

score 104 · Answer 15 · 2026-04-17 09:09:32

104

Views

The sum $\frac{1}{1!2004!} + \frac{1}{3!2002!} + \frac{1}{5!2000!} + ... + \frac{1}{2003!2!} = \frac{(2^a - 1)}{b!}$.

Published on 17 Apr 2026 - 9:09

List Question

Simple arithmetic word problem whose solution I don't understand

Prove some member of the sequence $7, 77, 777, 7777, \dots$ is divisible by $2019$.

For every $x\in[\frac{3}{2}, 5]$ prove that: $(\sqrt{2x-3}+\sqrt{15-3x}+2\sqrt{x+1})^2<71.25$

Permute the entries of each column so that the row sums have absolute value $\le 2$.

If $g(x)=\frac{P(x)}{x^2-4}$, $\lim_{x\rightarrow\infty}g(x)=5$, and $\lim_{x\rightarrow2}g(x)=\frac{9}{4}$, find P(x) (Sweden 1950)

The rays $PX$ and $PY$ cut off arc $AB$ and $CD$ of a circle with radius $4$ .

Question on tiling of a $2n\times 2n$ square

Find all values of a for which the following system has a solution, no solution and infinitely many solution.

Tricks for questions involving finding integer solutions for a fraction which contains variables

General substitution method for solving first order recurrence relations with non-linear coefficients

How many times would you have to draw from a deck before there's at least a 90% chance you've drawn the Ace of Spades 5 times (with replacement)

If $z_1, z_2$ complex numbers and $u\in(0, \frac{π}{2})$ Prove that: $\frac{|z_1|^2}{\cos^2u}+\frac{|z_2|^2}{\sin^2u}\ge|z_1|^2+|z_2|^2+2Re(z_1z_2)$

Prove that $F(x,y)=(x-4y,2x+3y)$ is bijective

Alphabetical arrangement of 5 letters - MUSIC

The sum $\frac{1}{1!2004!} + \frac{1}{3!2002!} + \frac{1}{5!2000!} + ... + \frac{1}{2003!2!} = \frac{(2^a - 1)}{b!}$.

Trending Questions

Popular # Hahtags

Popular Questions