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Homework Help: Integration of a reciprocal function

  1. Jun 4, 2012 #1
    1. The problem statement, all variables and given/known data
    Evaulate the integral of (4-x2)-3/2.

    2. Relevant equations
    integration by parts

    3. The attempt at a solution
    Too long to write it all down, but I used the aforementioned equations. Basically, I'd like somebody to give me a hint about how or where to start, since everything I tried so far hasn't worked.
  2. jcsd
  3. Jun 4, 2012 #2
    Is this an indefinite integral?
  4. Jun 4, 2012 #3
    yes, it is
  5. Jun 4, 2012 #4


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    Do you know the rules of substitution ?
  6. Jun 4, 2012 #5


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    Staff Emeritus
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    Gold Member

    What did you use for the substitution? What did you use for the parts of the integration by parts?

    We can give much better help if you show us what you've done. Besides that, it's part of the rules for Homework help in this Forum.
  7. Jun 4, 2012 #6
    Yes, that's what I meant by u-replacement. Sorry if that wasn't clear.
  8. Jun 4, 2012 #7


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    Generaly speaking, integrals that involve roots of squares call out for a trig substitution. What happens if you let [itex]x= 2 sin(\theta)[/itex]?
  9. Jun 4, 2012 #8
    I've used 4-x2, (4-x2)-1/2 and (4-x2)
    as a substitution.
  10. Jun 4, 2012 #9
    Thanks HallsofIvy, I got it now. It's x/(4(4-x2)1/2).
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