Upgrade subject to access all content

Find all values of $x$ for which the following series converges.

$$\sum _{ n=1 }^{ \infty }{ \cfrac { { 3 }^{ n }{ x }^{ n } }{ n+1 } } $$

$ \left(-\cfrac{1}{3}, \cfrac{1}{3}\right)$

$\left[-\cfrac{1}{3},\cfrac{1}{3}\right]$

$\left(-\cfrac{1}{3},\cfrac{1}{3}\right]$

$\left[-\cfrac{1}{3},\cfrac{1}{3}\right)$