Does the Maximum of Two Convergent Series Also Converge?

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Homework Statement


Let Ʃ from n=1 to ∞ an and Ʃ from n=1 to ∞ bn be convergent series, with an\geq0 and bn\geq0 for all n\inN. Show that the series Ʃ from n=1 to∞ max(an,bn) converges.



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I'm guessing it's got something to do with the cauchy criterrion for convergence of series but I'm not sure where to begin? Any hints would much appreciated
 
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I would write

2 max(a,b)=a+b+|a-b|

or

max(a,b)<=a+b

Either of which obviously converge.
 
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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