Proving the Inequality: 1/(n+1) < ln(1+(1/n)) < 1/n for f(x) = 1/(1+x)

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prove that

1/(n+1) < ln (1+(1/n)) < 1/n

considering lower and upper approximations to the integral of f(x) =1/(1+x) over an appropriate doman.
 
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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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