I've been having some problems with these two series.
$\begin{align}&\sum_{n=0}^\infty (-1)^n\frac{n}{3^n}\\&\sum_{n=0}^\infty \left(\frac{(-1)^n}{n+1}+\frac{(-1)^n}{n+2}\right)\end{align}$
The first seems similar to a geometric series but I don't know what to do with that extra $n$.
The second I really just don't know what to do either.
I'd really appreciate any help you can give me, thanks!