Convergence of Series: Using the Root Test to Prove Convergence

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Homework Statement



\text{Show that }\sum_{n=1}^{\infty} \left( \frac{e}{n} \right) ^n \text{converges.}

The Attempt at a Solution



I think we should use the root test.

\lim_{n \to \infty} \sqrt[n]{\left( \frac{e}{n} \right) ^n} = \lim_{n \to \infty} \frac{e}{n} = 0 < 1

So the series is convergent.


Does it look alright?

Thanks in advance.
 
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