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Homework Help: Int( X/(x+2)^(1/4)) substitutions

  1. Sep 24, 2010 #1
    1. The problem statement, all variables and given/known data
    I'm having a problem with U-Substitution. I get the simple stuff and the trig substitutions, but this problem has been bugging me.
    Int( X/(x+2)^(1/4))


    2. Relevant equations



    3. The attempt at a solution
    I first tried u=x+2 and then du=dx. I then solved for x, where x= U-2.

    That put me at Int( (u-2)/(u^(1/4)). And that's where I don't really know how to go on.
     
  2. jcsd
  3. Sep 24, 2010 #2

    rock.freak667

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    Homework Helper

    Re: U-Substitution

    You can split (u-2)/u1/4 as u/u1/4-2/u1/4.
     
  4. Sep 24, 2010 #3
    Re: U-Substitution

    So split it then integrate it from there?
     
  5. Sep 24, 2010 #4
    Re: U-Substitution

    Thanks for the help. I got:
    (4/7)(x+2)^(7/4) - (8/3)(x+2)^(3/4) +C.
     
  6. Sep 24, 2010 #5

    rock.freak667

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    Homework Helper

    Re: U-Substitution

    That should be correct.
     
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