Integral from 1 to infinity of 1 / xln(third root of x)

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Homework Statement



Integral from 1 to infinity of 1 / xln(third root of x)

2. Homework Equations

n/a

3. The Attempt at a Solution

I tried to find if it diverged and then got lost after that

Homework Equations





The Attempt at a Solution

 
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if it diverges then that's the final answer. But can you post your work? maybe you did a mistake. But I think it is supposed to diverge.
 
well you see there bob I am not too sure how to get started and what to do with the ln
 
If you don't know what to do, then you don't know it diverges, right? Try a substitution u=ln(x).
 
Dick: I did u = ln(x) and du = 1/x

so int from 1 to 0 ln(third root of u)du

= - in from 0 to 1 ln(third root of u)du

I always mix up these substitutions.
 
Note: \log_a b^x = x \log_a b where a, b and x are real numbers, (a,b) > 0.
 
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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