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I'm deeply impressed by mathematics.


1d
accepted Prove that for all non-negative integers $m,n$, $\frac{(2m)!(2n)!}{m!n!(m + n)!}$ is an integer.
Dec
15
comment Strategies to denest nested radicals.
isibang.ac.in/~sury/ramanujanday.pdf
Dec
12
comment Old oxford scholarship question: $a^ab^b \ge a^bb^a$
Ah, i see, i thought it only apply to positive reals.
Dec
12
comment Old oxford scholarship question: $a^ab^b \ge a^bb^a$
What if $\log a$ or $\log b\leq0$? Better assume $a\geq b$, and use $\log_{b/2}$.
Dec
9
awarded  Caucus
Dec
4
comment Prove that orientable surface has differentiable normal vector
Can you please give me a bit more hint of next steps in each direction?
Dec
4
accepted Presentation of a group: Show that $\langle a|a^2\rangle =\{1,a\}$.
Dec
4
accepted Let $H$ be subgroup of $G$, $a,b\in G$, how that $Ha=Hb$ iff $ab^{-1}\in H$.
Dec
3
asked Prove that orientable surface has differentiable normal vector
Nov
18
accepted When will $AB=BA$?
Nov
5
awarded  Nice Question
Sep
30
awarded  Explainer
Sep
24
awarded  Autobiographer
Sep
21
comment Presentation of a group: Show that $\langle a|a^2\rangle =\{1,a\}$.
Ya, I will work hard, thanks for your help.
Sep
20
comment Presentation of a group: Show that $\langle a|a^2\rangle =\{1,a\}$.
So what exactly $\{N,Na\}$ is? Is it $\{\{1,a^{\pm2},a^{\pm4},...\},\{a^{\pm1},a^{\pm3},a^{\pm5},..\}\}$?
Sep
20
awarded  Notable Question
Sep
20
comment Presentation of a group: Show that $\langle a|a^2\rangle =\{1,a\}$.
$\{N,Na\}=F$?????
Sep
20
comment Presentation of a group: Show that $\langle a|a^2\rangle =\{1,a\}$.
So $N=\{1,a^{\pm 2},a^{\pm 4},...\}$?
Sep
20
revised Presentation of a group: Show that $\langle a|a^2\rangle =\{1,a\}$.
added 213 characters in body
Sep
20
revised Presentation of a group: Show that $\langle a|a^2\rangle =\{1,a\}$.
deleted 1 character in body