Calculating integral by differentiating first

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Homework Statement


Calculate the integral
I = \int (t^x - 1)/ln(t) dt, boundaries: 0 \leq t \leq 1, x \geq 0
by differentiating first with respect to x.

Homework Equations


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The Attempt at a Solution


I have no idea how to solve this, but it's on our sample exam and there are no solutions... =/ Differentiating with respect to x gives me:
d/dx((t^x - 1)/ln(t)) = ln(t)e^(xln(t))/ln(t) + 0 = e^(xln(t)) = t^x
Can I use this in any way? Maybe substitute t^x in the integral with d/dx(t^x - 1)/ln(t)?
Any clues appreciated!

 
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Remember that the Leibniz Rule gives you

\frac{d}{dx}\int_0^1{\frac{t^x-1}{ln(t)}dt}=\int_0^1{\frac{d}{dx}\left(\frac{t^x-1}{ln(t)}\right)dt}=\int_0^1{t^xdt}

Now, the right-hand side looks like an easy integral...
 
Very nice. Physmatics, becareful to distinguish between the derivatives of x^a and a^x.
 
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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