Complicated Limit from Analysis

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I need some help showing the following limit. I don't really know where to start, and I was just looking for a quick tip or two to begin the proof. Thanks!

Problem:

\lim_{n\rightarrow\infty} \sqrt[n]{\alpha^n+\beta^n} = max (\alpha,\beta)
 
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1. From symmetry, you can assume that alpha >= beta.
2. Now you need to prove that the limit is alpha.
3. Remember the trick where you multiply and then divide by same factor (Think, what factor should it be?).
 
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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