# Math Help - Integral Calculus.

1. ## Integral Calculus.

Hi there mathematicians.. I just wanna ask some help for solving this problem. I got stuck when answering this..
what would be the best approach for solving this?
integrate lnx ln(1-x) dx, from 0 to 1.

2. ## Re: Integral Calculus.

Here's one way...

Spoiler:

... gets a bit hairy, but I think you can evaluate using Polylogarithm -- from Wolfram MathWorld

... where (key in spoiler) ...

Spoiler:

... is the product rule, where, straight continuous lines are differentiating downwards with respect to x. (I've used the triple version of the rule as well - see wikipedia.)

... is lazy integration by parts, doing without u and v.

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