Chapter 9.2, Problem 33E

Combining power series Use the geometric series

$f(x)=\frac{1}{1-x}={\displaystyle \underset{k=0}{\overset{\infty }{\sum }}{x}^k},\text{for}\left|x\right|<1,$

to find the power series representation for the following functions (centered at 0). Give the interval of convergence of the new series.

33. $p(x)=\frac{4x^{12}}{1-x}$