Easy way to show $D^n/S^{n-1}\cong S^n$
35948
How to prove $D^n/S^{n-1}\cong S^n$?
8192
Simple proof of showing the Harmonic number $H_n = \Theta (\log n)$
141909
Prove ${2}^{n}\cdot(2m+1)-1 $ is invertible
62254
Show $F_{n+1} \cdot F_{n-1} = F_n^2 + (-1)^n$ for all $n \in \mathbb{N}$
23590
Show that $\gcd\left(\frac{a^n-b^n}{a-b},a-b\right)=\gcd(n d^{n-1},a-b)$
26197
$B^n/S^{n-1}$ is homeomorphic to $S^n$
12469
$\varphi$ in $\operatorname{Hom}{(S^1, S^1)}$ are of the form $z^n$
5287
Representing every positive rational number in the form of $(a^n+b^n)/(c^n+d^n)$
141010
Computing $n$-th external power of standard simplectic form
135046
Can this quick way of showing that $K[X,Y]/(Y-X^2)\cong K[X]$ be turned into a valid argument?
11003
Proving that $G/N$ is an abelian group
7575
Show the commutator subgroup of $S_{n}$ is $A_{n}$ for $n \geq 5$
95061
Proving that $2^{2\cdot 3^{n-1}}\equiv 1+3^n\pmod{3^{n+1}}$ for every natural $n$
115726
For $p,q$ prime and $p \neq q$ show that $C_p \times C_q \cong C_{pq}$
1837
Showing that $1^k+2^k + \dots + n^k$ is divisible by $n(n+1)\over 2$
27629
How to prove that $S^{2n+1}/S^1$ is homeomorphic to $\mathbb CP^n$ under a given identification
115204
Show that SO(n) is a normal subgroup of O(n)