I am having a difficult time seeing how [itex]\sum_{n=0}^{\infty} ((-1)^n + 1)x^n[/itex] is equivalent to [itex]2\sum_{n=0}^{\infty} x^{2n}[/itex](adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Power Series

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