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Homework Help: Evaulating this Integral

  1. Jan 22, 2012 #1
    1. The problem statement, all variables and given/known data

    http://img528.imageshack.us/img528/356/hwhelp.png [Broken]

    2. Relevant equations

    http://img407.imageshack.us/img407/3696/uanddu.png [Broken]

    3. The attempt at a solution
    This is the answer I got. I was wondering how du replaces the circled part of the question.

    http://img546.imageshack.us/img546/8975/hwanswer.png [Broken]
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Jan 22, 2012 #2
    I just came up with this information now. Is it right?

    http://img851.imageshack.us/img851/3763/uandupart2.png [Broken]
    Last edited by a moderator: May 5, 2017
  4. Jan 22, 2012 #3


    Staff: Mentor

    You have
    [tex]du = \frac{e^{\sqrt{x}}}{2\sqrt{x}}dx = \frac{1}{2\sqrt{x}e^{-\sqrt{x}}}dx[/tex]

    The part you have circled (and including dx) is 2du.
    Last edited by a moderator: May 5, 2017
  5. Jan 24, 2012 #4
    Thanks, I get it now.
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