Ʃ n=1 to infinity of cos(n∏)(adsbygoogle = window.adsbygoogle || []).push({});

letting an=cos(n∏), I rewrote this as (-1)^n=an.

Using the nth term test i let the limit as n->∞ go to infinity. This value bounces back and forth between positive and negative, but I know clearly the value =/= 0, therefore it diverges by the nth term test.

Is there anything I should add to my proof?

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# Is my proof of this sequence's divergence good enough?

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