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Finding the antiderivative of a fractional prob

  1. Jan 16, 2009 #1
    I am suppose to evaluate this integral by using substitution

    I will be very thankful if someone were able to tell me a strategy in antiderivitating fractional problems.

    What I did:
    I set u=-0.5x

    therefore i got (-1/0.5)((e^u)/(1-e^u))du
    I am unsure of what the next step would be

    Please help
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jan 16, 2009 #2


    Staff: Mentor

    Assuming this is the problem:
    [tex]\int \frac{e^{-.5x}}{1 - e^{-.5x}} dx[/tex]

    Let u = 1 - e-.5x

    Then your integral is more or less
    [tex]\int \frac{du}{u}[/tex]
    which is pretty easy.
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