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Homework Help: Evaluate the Integral

  1. Oct 4, 2013 #1
    1. The problem statement, all variables and given/known data

    Hi guys, so I've been having some trouble with this specific integral, and would like some help on how to solve it.


    2. The attempt at a solution


    Next stage I'm sort of confused because I've never encountered two variables with "u".
    Last edited: Oct 4, 2013
  2. jcsd
  3. Oct 4, 2013 #2


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    With you u substitution, all you have done is replace 'x' with 'u'. You haven't done any essential simplification to the integrand.

    I would suggest looking at integration by parts. If you can find candidates for u and v with parts, then further substitution might be warranted.
  4. Oct 4, 2013 #3
    Yeah I wasn't sure if I should substitute more lol or just go through with algebra. Thanks.
  5. Oct 4, 2013 #4
    Actually usub does work. Re write e^x in the denominator as e^-x times the squareroot expression. u=e^-x+1. does it looks like du could be written in terms of e^-x?
  6. Oct 4, 2013 #5
    I figured it out

  7. Oct 4, 2013 #6


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