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Homework Help: Integral of 2/((e^(-x))+1)

  1. May 25, 2009 #1
    1. The problem statement, all variables and given/known data

    integral of 2/((e^(-x))+1)

    2. Relevant equations

    how do you do this?

    3. The attempt at a solution

    no freaking clue! this is the BS i came up with

    2(x-ln(e^-x + 1) + C)
  2. jcsd
  3. May 25, 2009 #2
    You can rewrite the integrand and then use a simple substitution. Hint: multiply the numerator and denominator by e^x and then simplify.
    Last edited: May 25, 2009
  4. May 25, 2009 #3
    so then...i want to find the integral of e^x/(e^x + 1)...and i think i want to use substitution? u = e^x + 1. but then i do something wrong somewhere...i'm getting retarded answers...
  5. May 25, 2009 #4


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    Homework Helper

    If [itex]u=e^x+1[/itex] then du=?
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