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I'm deeply impressed by mathematics.


Jan
5
awarded  Nice Answer
Jan
4
accepted Computation of a indefinite integral: $ \int \frac {dx} {x^n-1}$
Jan
4
accepted How to better define $f(n)=\begin{cases} 1,&n\text{ even} \\ 0, &n\text{ odd}\end{cases}$?
Jan
3
comment Computation of a indefinite integral: $ \int \frac {dx} {x^n-1}$
No need to add 1/(z+1) if z even , right?
Jan
3
asked How to better define $f(n)=\begin{cases} 1,&n\text{ even} \\ 0, &n\text{ odd}\end{cases}$?
Jan
2
comment Computation of a indefinite integral: $ \int \frac {dx} {x^n-1}$
There isn't any, it's indefinite...
Jan
2
revised Computation of a indefinite integral: $ \int \frac {dx} {x^n-1}$
deleted 2 characters in body
Jan
2
comment Computation of a indefinite integral: $ \int \frac {dx} {x^n-1}$
Thanks, corrected.
Jan
2
asked Computation of a indefinite integral: $ \int \frac {dx} {x^n-1}$
Dec
21
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 If both $a,b>0$, then $a^ab^b \ge a^bb^a$
Ah, i see, i thought it only apply to positive reals.
Dec
12
comment If both $a,b>0$, then $a^ab^b \ge a^bb^a$
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