Reputation
27,850
Next tag badge:
99/100 score
66/20 answers
Badges
2 23 62
Newest
 calculus
Impact
~461k people reached

12h
answered Is there a nice expression for $f(x) = (1+x)(1+x^2)(1+x^3)\cdots$
13h
comment Find the limit $\lim\limits_{n\to \infty}\sum\limits_{k=1}^{n}\left(\frac{k}{n^2}\right)^{\frac{k}{n^2}+1}$
And by grouping into groups of size $2^n$, $H_n < \log_2(n)$.
14h
comment Find the limit $\lim\limits_{n\to \infty}\sum\limits_{k=1}^{n}\left(\frac{k}{n^2}\right)^{\frac{k}{n^2}+1}$
Also, $n^{1/n} < 1+c\log(n)/n$, so $1/n^{1/n} > 1-d\log(n)/n$ for some real $c$ and $d$ for large enough $n$.
15h
comment Why doesn't quadratic formula lead to a the correct factored form of the original equation?
You mean $2x^2-3x-1$.
15h
answered Polynomial approximation for $f$ induces an approximation to $\sqrt f$?
1d
answered Prove a lower bound for $\sum_{i=1}^n i^2$
1d
comment Find the series: $\frac{-1}{4}+\left(\frac12+\frac14+\frac28+\frac3{16}+\frac5{32}+\cdots\right)$
A nice, basic solution. This would serve as a good introduction to the more general generating function approach.
1d
comment geometrical problem on triangle
These votes to close for "missing context or other details" annoy me. This seems like a perfectly reasonable question. I don't see what context is missing.
1d
answered geometrical problem on triangle
1d
comment geometrical problem on triangle
It means the measure of the angle.
2d
revised Can you verify this inequality $\binom {m^2} {m-1} \geq m^{m-1} \geq 2^{n/2}/n$
corrected error
2d
comment Can you verify this inequality $\binom {m^2} {m-1} \geq m^{m-1} \geq 2^{n/2}/n$
You are right - my mistake. I'll fix that. Thanks.
Aug
30
answered Solving general linear ODE $\sum_{k=0}^n y^{(k)}=0$
Aug
29
comment Ways Of Finding Primes and If they are efficient
What do you mean "it is a whole number"? What is "it"?
Aug
29
comment Solving ODE y'(x)=2 x y(x), using power expansion
I fixed that. Thanks.
Aug
29
revised Solving ODE y'(x)=2 x y(x), using power expansion
additional stuff
Aug
29
answered Solving ODE y'(x)=2 x y(x), using power expansion
Aug
28
answered Can you verify this inequality $\binom {m^2} {m-1} \geq m^{m-1} \geq 2^{n/2}/n$
Aug
28
comment Can you verify this inequality $\binom {m^2} {m-1} \geq m^{m-1} \geq 2^{n/2}/n$
$m \approx (n/2)/log(n/2) > \sqrt{n}$.
Aug
28
answered Can you verify this inequality $\binom {m^2} {m-1} \geq m^{m-1} \geq 2^{n/2}/n$