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Math Help - Stuck on an Integration

  1. #1
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    Stuck on an Integration

    \int x^4 lnx

    So I used integration by parts
    u=lnx \ du= \frac1x \ dv= x^4 \ v=\frac15 x^5

    so using the formula
    UV-\int VdU

    I get
    lnx \frac15 x^5 - \frac15 \int \frac{x^5}x

    Here is where I get stuck, I am not sure how i should approach the integration. If I had the reciprocal it would be no problem.
    \int \frac{x^5}x

    any help is appreciated, thanks!
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  2. #2
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    Hello, Spoolx!

    Happy New Year!

    Don't kick yourself too hard . . .


    \displaystyle\int \frac{x^5}{x}\,dx

    Here is where I get stuck.

    . . \dfrac{x^5}{x} \:=\:x^4

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  3. #3
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    Quote Originally Posted by Soroban View Post
    Hello, Spoolx!

    Happy New Year!

    Don't kick yourself too hard . . .



    . . \dfrac{x^5}{x} \:=\:x^4


    wow.. I cant believe I missed something that simple, sometimes when you try too hard you miss the easiest things...
    Thanks a bunch!

    Happy New Year to you also!
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