Logarithmic Differentiation for (1+x)^(1/x): Finding dy/dx

chapsticks
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Homework Statement



Use logarithmic differentiation to find dy/dx for y=(1+x)^(1/x).

Homework Equations


dy/dx


The Attempt at a Solution


ln y = ln (1+x)^(1/x)
= (1/x) ln (1+x)
(dy/dx) /y = (-1/x^2)(ln(1+x) + (1/x)(1/(1+x)

dy/dx = y [(-1/x^2) ( ln(1+x) + x/(1+x) ]
or (-1/x^2)( ln(1+x) + x/(1+x) ) (1+x)^(1/x)
 
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chapsticks said:

Homework Statement



Use logarithmic differentiation to find dy/dx for y=(1+x)^(1/x).

Homework Equations


dy/dx


The Attempt at a Solution


ln y = ln (1+x)^(1/x)
= (1/x) ln (1+x)
(dy/dx) /y = (-1/x^2)(ln(1+x) + (1/x)(1/(1+x)

dy/dx = y [(-1/x^2) ( ln(1+x) + x/(1+x) ]
or (-1/x^2)( ln(1+x) + x/(1+x) ) (1+x)^(1/x)

Do you have a question?
 
Yes, I want to check my work if it's correct.
 
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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