# Math Help - Homework

1. ## Homework

can someone find $\sum-{i=1}^{\infty}1\frac{i}$??

thanks

2. Your LaTeX-code isn't right but from the code I suspect you mean

$\sum\limits_{i = 1}^{ + \infty } {\frac{1}{i}}$

If so, this sum (harmonic series) diverges.

3. Sorry i mean this sum:
$\sum-{i=1}^{\infty}1\frac{{i}^2}$??

4. Still not there, do you mean

$
\sum\limits_{i = 1}^{ + \infty } {\frac{1}{i^2}}
$

?

5. yes thanks

6. That's a very well-known problem with the nice answer $\frac{\pi^2}{6}$ but it's not trivial to find this result.

This pdf file contains 14 (!) different proofs for it, some a bit more understandable than others, depending on your mathematical background.

7. thank u sooooooooooooooo much

8. You're welcome