Can someone start me out with this? (lnx)^2 dx I thought to make u = lnx, but then du = dx/x... I cant use it with that x, can I? thanks!
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Originally Posted by Morgan82 Can someone start me out with this? (lnx)^2 dx I thought to make u = lnx, but then du = dx/x... I cant use it with that x, can I? thanks! See here
Originally Posted by Morgan82 Can someone start me out with this? (lnx)^2 dx I thought to make u = lnx, but then du = dx/x... I cant use it with that x, can I? thanks! Remember that $\displaystyle \ln^2{x} = \ln{x}\cdot\ln{x}$. So use integration by parts. You will need to make use of the fact that $\displaystyle \int{\ln{x}\,dx} = x\ln{x} - x$.
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