# Thread: derechlet theorem special points?

1. ## derechlet theorem special points?

http://i49.tinypic.com/hur98w.jpg
i found the series of the given function
and i need to find the value of
$
\sum_{n=1}^{\infty}\frac{\sin (n)}{n}
$

so i used derechlet
$
f(0)=\frac{h^2}{\pi}(\pi-h)-\sum_{n=1}^{\infty}\frac{h^2}{\pi}\frac{sin(hn)}{n }
$

but on x=0 f(0) could be 0 or $h^2$ so i don know what to put instead of f(0)

and i dont how to decide what value to put instead of h