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

Show if true:

[tex]\sum_{i=1}^{n-1}e^{2 \pi ift}=\frac{e^{2 \pi ifn}-1}{e^{2 \pi if}-1}=e^{\pi if(n-1)}\frac{e^{\pi ifn}-e^{-\pi i f n}}{e^{ \pi if}-e^{-\pi if}}\\\\\\\\[/tex]

2. Relevant equations

I'm really stuck here, just looking for a suggestion as to what equation to use...

Can I take the log? How can I get the sum inside the exponential?

3. The attempt at a solution

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# Homework Help: How can I get the sum inside the exponential?

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