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Math Help - another EZ Integral

  1. #1
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    another EZ Integral

    By easy, I mean for people that are good at this. I spent 30 minutes thinking prior to posting here

    <br />
\frac{1}{xln^3x}dx<br />

    This looks like u = ln(x) or something but that extra x is messing me up
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  2. #2
    Behold, the power of SARDINES!
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    Quote Originally Posted by TYTY View Post
    By easy, I mean for people that are good at this. I spent 30 minutes thinking prior to posting here

    <br />
\frac{1}{xln^3x}dx<br />

    This looks like u = ln(x) or something but that extra x is messing me up
    You have the correct substituion

    u=\ln(x) \implies du=\frac{1}{x}dx

    putting these into the integral gives

    \int \frac{1}{u^3}du=\int u^{-3}du

    Good luck.
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  3. #3
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    Quote Originally Posted by TheEmptySet View Post
    You have the correct substituion

    u=\ln(x) \implies du=\frac{1}{x}dx

    putting these into the integral gives

    \int \frac{1}{u^3}du=\int u^{-3}du

    Good luck.
    I'm actually a little bit upset that it was that easy. Thank you though - I do appreciate it
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