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

[tex] \left\{ e^{n r \pi i}: n \in \textbf{Z} \right\} , r \in \textbf{Q} [/tex]

I'm trying to show that this set is finite.

2. Relevant equations

3. The attempt at a solution

Other than the fact that these points lie on the unit circle in the complex plane, I'm not sure where to start. Any direction would be helpful. clearly there's a way to choose r or n and use periodicity to show a finite set of points for this sets. But I'm not sure how r and n could be chosen.

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# Homework Help: Finite set

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