Find the antiderivative of the following problem Find the antiderivative of $\pi(\frac{4}{y^2})$.
This has to do with a volume problem. And I'm using the disk method to solve. So the pi needs to incorporated. 

$\int \frac{4\pi}{y^2}dy = 4\pi\int y^{-2}dy=4\pi\frac{y^{-1}}{-1}=-\frac{4 \pi}{y} + c $
Here $c$ is the constant of integration as the integral is indefinite.
