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**director** Hi all, I have the following function $\displaystyle f(z) = \frac{1}{(z^2 + z + 1)^2}$ and I need to find the residue at the double pole $\displaystyle z = (-1)^{\frac{2}{3}}$. Any tips? I'm hoping to not have to use the Laurent expansion for this. I know that $\displaystyle (z^2 + z + 1) = \frac{(1-z)}{(1-z^3)}$. I'm aware of a limit formula for higher order poles but I don't know how to manipulate the function to get it in that form. Maybe that's not even needed. Thanks!