I need to compute the residue for $\displaystyle \frac{e^{-z}}{(z-1)^2}$. I'm going to be using it for Cauchy's residue theorem to evaluate the integral around the circle |z| = 3, so there is obviously a singularity at z=1. I'm confused how to manipulate the fraction and bring in series so that I can see what the coefficient on the $\displaystyle \frac{1}{z-1}$ term. Thank you.