Holomorphic Around a Pin Integral

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I have a question I thought was going to be simple, but I have no idea how to go about actually solving it. I've shown it's holomorphic other than at 0, but I can't use the Cauchy Integration Formula and so don't know how to approach this problem.

Counterclockwise Contour Integral for |z| = 1

(cos z)dz/z^3

How might I go about solving this? I'm assuming I need the Cauchy Integration formula but I can't think of an a to use...

Thanks!

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I've figured it out. Use Cauchy's Formula for higher n, namely:

The nth derivative of f(z) = n!/ipi contour integral f(z)dz/(z-a)^(n+1)