I was having a debate with a friend about how to show the following limit.(adsbygoogle = window.adsbygoogle || []).push({});

[tex] \lim_{n \to \infty} \cos( \frac{2 \pi}{2n - 2} )^n = 1 [/tex]

I claim that you can just hand-wavingly say that since cosine of 0 is 1, and 1^infinity is 1, the limit is 1. He claims I need to show this using some sort of limit theorem (I don't want to get into delta-epsilons).

Is there a cool limit theorem I can use?I

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# An interesting limit

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