Exercise 7.14 part 3 from https://files.acrobat.com/a/preview/bfa73f6f-a5bb-4790-8177-7a63da52655e
Prove that $\sum\frac{2^{{(-1)}^n}}{(\sqrt{n}+e)^3}$ converges.
Converges of $\sum\frac{2^{{(-1)}^n}}{(\sqrt{n}+e)^3}$
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sequences-and-series
convergence
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1 Answers
2
Hint:
Comparison test: $$\frac{2^{(-1)^n}}{(\sqrt n+\mathrm e)^3}\le\frac{2}{n^{3/2}}.$$