# Math Help - Power Series

1. ## Power Series

Can anyone tell me how

$\sum_{n=1}^{\infty }\frac{(-1)^{n}}{n3^{n}}(2-5)^{n}=\sum_{n=1}^{\infty }\frac{1}{n}$ ?

and also how to get this expression typed in LaTex to appear correctly?
$$\sum_{n=1}^{\infty }\frac{(-1)^{n}}{n3^{n}}(2-5)^{n}=\sum_{n=1}^{\infty }\frac{1}{n}$$

2. Originally Posted by tashbo
Can anyone tell me how

$\sum_{n=1}^{\infty }\frac{(-1)^{n}}{n3^{n}}(2-5)^{n}=\sum_{n=1}^{\infty }\frac{1}{n}$ ?
Note that $(2-5)^n=(-3)^n=(-1)^n(3^n)$