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Homework Help: Evaluate improper integral

  1. Apr 26, 2010 #1
    1. The problem statement, all variables and given/known data

    evaluate

    [tex]\int[/tex] [tex]\frac{1}{(1+x)\sqrt{x}}[/tex] dx

    2. Relevant equations

    N/A

    3. The attempt at a solution

    how to do this, i cant use partial fraction, and integration by part makes it harder i guess, maybe using substitution, but how T_T
    helpp
     
    Last edited: Apr 26, 2010
  2. jcsd
  3. Apr 26, 2010 #2
    Hi, do you have the answer?
     
  4. Apr 26, 2010 #3
    no, why?
     
  5. Apr 26, 2010 #4
    I tried to solve it through substitution, but I'm not sure if it's correct and would like to have it verified.
     
  6. Apr 26, 2010 #5
    can you tell me what substituion you are using please?
     
  7. Apr 26, 2010 #6

    Cyosis

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    Homework Helper

    When you have an integral like this always try a few substitutions instead of just staring at it. Obvious substitutions would be u=1+x and u=sqrt(x). I will let you decide which one is the useful one.
     
  8. Apr 26, 2010 #7
    I tried this:

    [tex]u = \sqrt{x}[/tex]

    [tex]u^2 = x[/tex]

    Can you take over from here?
     
  9. Apr 26, 2010 #8
    thanks, i got the idea. thank you very much
     
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