E.H.E's user avatar
E.H.E's user avatar
E.H.E's user avatar
E.H.E
  • Member for 9 years, 4 months
  • Last seen more than a week ago
22 votes

Exact Sum of Series

18 votes

Why is this integration method not valid?

14 votes

Value of this convergent series: $\frac{1}{3!}+\frac2{5!}+\frac3{7!}+\frac{4}{9!}+\cdots$

13 votes

Different ways to prove $\sum_{k=1}^\infty \frac{1}{k^2}=\frac{\pi^2}{6}$ (the Basel problem)

11 votes
Accepted

How do we integrate $(e^x + 2x)^2$?

11 votes
Accepted

Prove or disprove: $\sum_{k=1}^{\infty}\frac{\sqrt{k+1}-\sqrt{k}}{k\sqrt{k}}$ is convergent

10 votes
Accepted

Finding $\lim_{n\rightarrow \infty }\left(1-\frac{1}{n^2}\right)^n$

10 votes

Limits to infinity of a factorial function: $\lim_{n\to\infty}\frac{n!}{n^{n/2}}$

9 votes
Accepted

Proving $\int_{0}^{1}\sqrt{\frac{1-x}{1+x}}dx=\frac{π}{2}-1$

9 votes
Accepted

Why does $k^2+4k+4$ become $(k+2)^2$?

9 votes

Is there any difference in solutions between $x^7-1^7=0$ and $x^7-1=0$?

9 votes
Accepted

Solve $2x(1+\frac{1}{x^3})+7(1+\frac{1}{x})=0$ without cubic formulas and such

8 votes

Easier way to calculate the derivative of $\ln(\frac{x}{\sqrt{x^2+1}})$?

8 votes

How to solve this equation for $x$?$\left(\sqrt{2-\sqrt{3}}\right)^x + \left(\sqrt{2+\sqrt{3}}\right)^x = 2$

8 votes
Accepted

Does the series: $\sum_{n=1}^\infty \frac{2n+1}{n^2(n+1)^2}$ converge?

8 votes

How do I prove that $x^2 + y^2 = (x + y) ^2 – 2xy$ geometrically/intuitively?

8 votes

Limit of the sequence $\lim_{n\to\infty}{\sqrt[n]{4^n + 5^n}}$

8 votes

How to find the limit using L'Hôspital's Rule

8 votes

What is the value of $\frac11+\frac13-\frac15-\frac17+\frac19+\frac1{11}-\dots$?

7 votes
Accepted

finding out if two vectors are perpendicular or parallel

7 votes
Accepted

Proof $\sum_{n=0}^\infty \frac{n^2+3n+2}{4^n} = \frac{128}{27}$

6 votes

How to solve $4^x+\sin(x)=10$

6 votes

Finding the angle between two line equations

6 votes
Accepted

How to differentiate $x^2-|x^3|$?

6 votes

Limit for $(\frac{n}{n+1})^n$ to infinity

6 votes

Solving $\lim_{x\to-\infty}x^2\cdot e^x$ with L'Hopital

6 votes

Need to simplify ratio test: $\frac{(2(k+1))!}{(2k)!} $

6 votes

Test of being a rational number for $(1-\frac13+\frac15-\frac17+\cdots)/(1+\frac14+\frac19+\frac1{16}+\cdots)$

6 votes

Calculate: $\frac{1}{2! \cdot 2} + \frac{1}{4! \cdot 4} + \frac{1}{6! \cdot 8} + \frac{1}{8! \cdot 16} + ...$

6 votes
Accepted

Find the Maclaurin Series for $\frac{x}{x^2 + 1}$

1
2 3 4 5
27