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Math Help - Integrate

  1. #1
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    Integrate

    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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    Quote Originally Posted by Morgan82 View Post
    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
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  3. #3
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    Quote Originally Posted by Morgan82 View Post
    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 \ln^2{x} = \ln{x}\cdot\ln{x}.

    So use integration by parts.

    You will need to make use of the fact that \int{\ln{x}\,dx} = x\ln{x} - x.
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