Can the Definite Integral of (ln x)^n be Expressed Using Factorials?

razorfever
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Homework Statement


Show that the definite integral from 0 to 1 (ln x)^n dx = n!(-1)^n

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The Attempt at a Solution


i tried to integrate by parts and kept going on and on but i don't know how to incorporate the factorial in the answer ...
 
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When you integrated by parts, what did you get?
 
Rather than integrating by parts repeatedly, it may be simpler to try to use induction to show this result. You only need to integrate by parts once if you do that, so it may be easier for you to see your answer.
 
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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