Question

Real and positive sum of complex number in the unit circle

score 395 · Answer 1 · 2026-03-25 23:37:43

395

Views

Real and positive sum of complex number in the unit circle

Published on 25 Mar 2026 - 23:37

score 112 · Answer 2 · 2026-04-15 21:11:51

112

Views

Prove that $\sum _{cyc}\sqrt{1-\frac{\left(a+b\right)^2}{4}}\ge \sqrt{6}$

Published on 15 Apr 2026 - 21:11

score 94 · Answer 3 · 2026-04-14 21:01:49

Why the sum of first $1000$ terms of $\sum_{n = 0}^{\infty} \frac{4(-1)^n}{2n+1}$ differs from $\pi$ in only 3rd decimal place.

score 198 · Answer 4 · 2026-04-20 23:33:42

198

Views

Formula for sum of combinations

Published on 20 Apr 2026 - 23:33

score 98 · Answer 5 · 2026-03-25 23:13:10

98

Views

Prove that $\sum_{u = 1}^{N} \sum_{v=1}^{N} \left(\left[\sqrt{u^2-4v} \in Z\right]+\left[\sqrt{u^2+4v} \in Z\right]\right) = D \left(N\right)-1$

Published on 25 Mar 2026 - 23:13

score 146 · Answer 6 · 2026-04-17 01:17:48

146

Views

Prove $1-\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{2n-1}-\frac{1}{2n}=\frac{1}{n+1}+\frac{1}{n+2}+\frac{1}{n+3} +...+\frac{1}{2n}$

Published on 17 Apr 2026 - 1:17

score 324 · Answer 7 · 2026-04-08 17:18:47

324

Views

Computing a sum of fractions using sigma notation

Published on 08 Apr 2026 - 17:18

score 77 · Answer 8 · 2026-04-14 15:33:32

77

Views

Is there closed form solution for $\sum_{i=1}^N i*q^i(1-q)^{N-i}$

Published on 14 Apr 2026 - 15:33

score 105 · Answer 9 · 2026-03-25 04:42:05

105

Views

Inequality with 5 cyclic variables

Published on 25 Mar 2026 - 4:42

score 26 · Answer 10 · 2026-04-10 22:25:06

26

Views

Vanishing terms in Sumation of an orthoganl integral

Published on 10 Apr 2026 - 22:25

score 102 · Answer 11 · 2026-04-14 12:37:27

102

Views

How do I prove that $\sum_{i=3}^{n} \frac{i-2}{\binom{i}{2}} < \frac n 4$ for all natural $n > 3$?

Published on 14 Apr 2026 - 12:37

score 476 · Answer 12 · 2026-04-09 13:51:23

476

Views

Coupon collectors problem: variance calculation missing a term.

Published on 09 Apr 2026 - 13:51

score 117 · Answer 13 · 2026-04-12 14:43:45

117

Views

Concrete maths: converting a recurrence to a sum relation

Published on 12 Apr 2026 - 14:43

score 160 · Answer 14 · 2026-04-16 14:49:25

160

Views

Given a set of coins find number of way to get a sum

Published on 16 Apr 2026 - 14:49

score 32 · Answer 15 · 2026-04-12 22:02:25

32

Views

Optimizing FFTs using 3 summations.

Published on 12 Apr 2026 - 22:02

List Question

Real and positive sum of complex number in the unit circle

Prove that $\sum _{cyc}\sqrt{1-\frac{\left(a+b\right)^2}{4}}\ge \sqrt{6}$

Why the sum of first $1000$ terms of $\sum_{n = 0}^{\infty} \frac{4(-1)^n}{2n+1}$ differs from $\pi$ in only 3rd decimal place.

Formula for sum of combinations

Prove that $\sum_{u = 1}^{N} \sum_{v=1}^{N} \left(\left[\sqrt{u^2-4v} \in Z\right]+\left[\sqrt{u^2+4v} \in Z\right]\right) = D \left(N\right)-1$

Prove $1-\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{2n-1}-\frac{1}{2n}=\frac{1}{n+1}+\frac{1}{n+2}+\frac{1}{n+3} +...+\frac{1}{2n}$

Computing a sum of fractions using sigma notation

Is there closed form solution for $\sum_{i=1}^N i*q^i(1-q)^{N-i}$

Inequality with 5 cyclic variables

Vanishing terms in Sumation of an orthoganl integral

How do I prove that $\sum_{i=3}^{n} \frac{i-2}{\binom{i}{2}} < \frac n 4$ for all natural $n > 3$?

Coupon collectors problem: variance calculation missing a term.

Concrete maths: converting a recurrence to a sum relation

Given a set of coins find number of way to get a sum

Optimizing FFTs using 3 summations.

Trending Questions

Popular # Hahtags

Popular Questions