Question

What can I assume in this proof?

score 28 · Answer 1 · 2026-04-11 05:00:55

28

Views

What can I assume in this proof?

Published on 11 Apr 2026 - 5:00

score 146 · Answer 2 · 2026-03-26 04:09:29

146

Views

Evaluate $\int_{|z|=3} \frac{cos(\pi z)}{(z-2)^2(z+5)(z+1)} \ dz$

Published on 26 Mar 2026 - 4:09

score 1.2k · Answer 3 · 2026-04-01 14:43:54

1.2k

Views

Prove that $n$ is prime iff $\sigma(n)+\phi(n)= nd(n)$.

Published on 01 Apr 2026 - 14:43

score 38 · Answer 4 · 2018-10-02 01:44:09

38

Views

Is my proof $A \cup (B \cap C) \subseteq (A \cup B) \cap (A \cup C)$ right?

Published on 02 Oct 2018 - 1:44

score 243 · Answer 5 · 2026-03-25 23:25:39

243

Views

Write $\mathbb{Z}_{20}^{\times}$ as a product of p-power cyclic groups.

Published on 25 Mar 2026 - 23:25

score 117 · Answer 6 · 2026-03-25 06:06:49

117

Views

Is $(q^k n^2 \text{ is perfect }) \iff (D(q^k)D(n^2) = 2s(q^k)s(n^2))$ only true for odd perfect numbers $q^k n^2$?

Published on 25 Mar 2026 - 6:06

score 324 · Answer 7 · 2026-04-09 01:50:18

324

Views

Is the following proof correct? invertibility of a Fredholm operator with trivial kernel.

Published on 09 Apr 2026 - 1:50

score 120 · Answer 8 · 2026-03-26 07:35:35

120

Views

Showing that $\csc\left(\frac{1}{z}\right)$ does not have a Laurent series convergent in $B^{\circ}(0,r)$

Published on 26 Mar 2026 - 7:35

score 27 · Answer 9 · 2026-03-30 02:54:59

27

Views

What $\frac{d}{dt}[F(\gamma(t))]$ where $F\in C^1(\Bbb R^n,\Bbb R^n)$ and $\gamma\in C^1(\Bbb R,\Bbb R^n)$?

Published on 30 Mar 2026 - 2:54

score 1.6k · Answer 10 · 2026-03-29 14:02:56

1.6k

Views

Prob. 2 (d), Sec. 27, in Munkres' TOPOLOGY, 2nd ed: If $A$ is compact and $U$ is an open set containing $A$, then . . .

Published on 29 Mar 2026 - 14:02

score 41 · Answer 11 · 2026-04-10 07:14:52

41

Views

Need help with proving/understanding uniform convergence of derivatives of analytic function. (Proof Verification)

Published on 10 Apr 2026 - 7:14

score 87 · Answer 12 · 2026-03-26 09:17:40

87

Views

A modified and more direct version of Dedekind cut method to define a completion of $(P, <)$

Published on 26 Mar 2026 - 9:17

score 137 · Answer 13 · 2026-04-09 00:24:58

137

Views

Proving $a\sqrt{7}>\frac{1}{c}$, where $a$ is an integer and $c = \lceil\frac{a}{\sqrt{7}}\rceil-\frac{a}{\sqrt{7}}$

Published on 09 Apr 2026 - 0:24

score 350 · Answer 14 · 2018-10-02 17:44:36

350

Views

Prove that S is the disjoint union of intervals, whose total length is at least 1.

Published on 02 Oct 2018 - 17:44

score 86 · Answer 15 · 2018-10-02 21:57:13

86

Views

Proof for $\langle a,b\rangle=\langle a-b,a+b\rangle $ check.

Published on 02 Oct 2018 - 21:57

List Question

What can I assume in this proof?

Evaluate $\int_{|z|=3} \frac{cos(\pi z)}{(z-2)^2(z+5)(z+1)} \ dz$

Prove that $n$ is prime iff $\sigma(n)+\phi(n)= nd(n)$.

Is my proof $A \cup (B \cap C) \subseteq (A \cup B) \cap (A \cup C)$ right?

Write $\mathbb{Z}_{20}^{\times}$ as a product of p-power cyclic groups.

Is $(q^k n^2 \text{ is perfect }) \iff (D(q^k)D(n^2) = 2s(q^k)s(n^2))$ only true for odd perfect numbers $q^k n^2$?

Is the following proof correct? invertibility of a Fredholm operator with trivial kernel.

Showing that $\csc\left(\frac{1}{z}\right)$ does not have a Laurent series convergent in $B^{\circ}(0,r)$

What $\frac{d}{dt}[F(\gamma(t))]$ where $F\in C^1(\Bbb R^n,\Bbb R^n)$ and $\gamma\in C^1(\Bbb R,\Bbb R^n)$?

Prob. 2 (d), Sec. 27, in Munkres' TOPOLOGY, 2nd ed: If $A$ is compact and $U$ is an open set containing $A$, then . . .

Need help with proving/understanding uniform convergence of derivatives of analytic function. (Proof Verification)

A modified and more direct version of Dedekind cut method to define a completion of $(P, <)$

Proving $a\sqrt{7}>\frac{1}{c}$, where $a$ is an integer and $c = \lceil\frac{a}{\sqrt{7}}\rceil-\frac{a}{\sqrt{7}}$

Prove that S is the disjoint union of intervals, whose total length is at least 1.

Proof for $\langle a,b\rangle=\langle a-b,a+b\rangle $ check.

Trending Questions

Popular # Hahtags

Popular Questions