(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I need to prove that [tex]\sum_{n=1}^{∞}[1−Cos(n−1z)][/tex] is entire.

2. Relevant equations

3. The attempt at a solution

I know that I need to show that the series is differentiable for its whole domain, but I am not sure how to do that. Should I try to use the ratio test?

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# Homework Help: Complex Analysis: Entire Function Series

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