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Homework Help: Finding the indefinite integral

  1. Jan 17, 2012 #1
    1. The problem statement, all variables and given/known data
    [itex]\int[/itex](x^(1/3)/(x^(1/3)+1))dx


    2. Relevant equations
    I know I have to use u substitution
    u=x^(1/3)
    du=1/(3x^(2/3))dx


    3. The attempt at a solution
    I know that the denominator of the equation will be u+1, but I don't understand how to find the numerator because I thought it would just be u, but wolfram alpha says it's u^3?
     
  2. jcsd
  3. Jan 17, 2012 #2

    Dick

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    If x^(1/3)=u then x^(2/3)=u^2. So du=(1/(3*u^2))dx. Does that tell you where the extra two powers of u are coming from?
     
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