Residue of power series $\frac{1}{(1-z)^2}$
$$\frac{1}{(1-z)^2}$$
I have no idea where to begin. I’ve been stumbling around, but I always seem to get led back to where I started. I have tried expanding $\frac{1}{(1-z)^2}$ into it’s Laurent series and then calculate the Residue at $\zeta=-1$, but it didn’t seem to lead