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Math Help - Integration by parts

  1. #1
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    Integration by parts

    The question:
    Use integration by parts to evaluate the following integral

    \int ln(x) dx

    I'm not sure what to do, since this looks like a single part to me. I'm clearly missing something fundamental here. Thanks.
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  2. #2
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    The general form is

    \int u \, dv = u v - \int v \, du

    Let u=\ln x and dv=dx. What does this give you?

    Notice that if you work this problem this way, you do not have to know what the integral of \ln x is! Instead you only need to know the derivative of \ln x to compute du. That is the reason for using the method.
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  3. #3
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    Thanks dude!
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