Finding the Limit of a Convergent Sequence

StrangeCharm
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Homework Statement


Determine whether the sequence converges or diverges. If it converges, find the limit.
Here's the sequence: http://www4a.wolframalpha.com/Calculate/MSP/MSP89541ea2ag9dg617bcd6000050d52e94i67ei593?MSPStoreType=image/gif&s=39&w=66.&h=44.

Homework Equations


N/A

The Attempt at a Solution


I know that the sequence is convergent if the limit exists; however, I'm having difficulty finding the limit. I tried finding the limit of the sequence as n-->infinity using L'Hopital's rule, but that got messy. I'm not sure what to do, especially because of all the terms.
 
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StrangeCharm said:
I tried finding the limit of the sequence as n-->infinity using L'Hopital's rule, but that got messy..

Find lim_{n \rightarrow \infty} \frac{n}{n + \sqrt{n}} and then think about the effect of (-1)^{n+1}.
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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