Help with Determining the Limit of the Sequence Quesiton

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Homework Statement



Problem is attached in this post

Homework Equations



Problem is attached in this post


The Attempt at a Solution



Lim n(2^(1/n)-1) as n -> ∞

Lim (2^(1/n)-1)/(1/n) as n -> ∞ -> 0/0 -> Indeterminate Form -> L'Hopital's Rule

However, I can't seem to figure out how to get the derivative of the numerator.
 

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student93 said:

Homework Statement



Problem is attached in this post

Homework Equations



Problem is attached in this post


The Attempt at a Solution



Lim n(2^(1/n)-1) as n -> ∞

Lim (2^(1/n)-1)/(1/n) as n -> ∞ -> 0/0 -> Indeterminate Form -> L'Hopital's Rule

However, I can't seem to figure out how to get the derivative of the numerator.

Write 2^(1/n) as e^(log(2)/n). Now use the chain rule to find the derivative.
 
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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