Converting a Sum to a Riemann Sum and Finding its Limit

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Homework Statement



Find limn->∞ (1/n)(Ʃk=1 to n ln(2n/(n+k)))

Homework Equations


The Attempt at a Solution



I'm not sure if this is even a riemann sum at all, but I don't see what else it could be. I wanted to find the riemann portion first to get rid of the sigma notation then find the limit of everything, but I don't have any of the information I need to do the riemann sum or to convert it to an integral.
 
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I realize I need to be able to put it in a form of (b-a)/n Ʃ (a+(b-a)k/n), but I'm not sure how I can work with ln and manipulate it when everything is stuck in ln. Any tips?
 
If you can put it in the form of sum (1/n)f(k/n) for some function f then it's a Riemann sum of the function f(x) for x=0 to 1. What's f?
 
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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