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Homework Help: Integration by parts(?)

  1. Jul 23, 2011 #1
    1. The problem statement, all variables and given/known data
    Hi

    There is a step in my book, which I can't follow. It is the following

    [tex]
    \int_0^1 {w\left( {\frac{{d^2 u}}{{dx^2 }} - u + x} \right)dx} = \int_0^1 {\left( { - \frac{{dw}}{{dx}}\frac{{du}}{{dx}} - wu + xw} \right)dx} + \left[ {w\frac{{du}}{{dx}}} \right]_0^1
    [/tex]

    I thought they might be using integration by parts, but that doesn't seem to be correct. Any help is greatly appreciated.

    Best,
    Niles.
     
  2. jcsd
  3. Jul 23, 2011 #2

    ehild

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    Homework Helper

    The first term, w u" is integrated by parts.

    ehild
     
  4. Jul 23, 2011 #3
    I see, thanks!
     
  5. Jul 23, 2011 #4
    Does that answer your question?
    If not, start to integrate the first term, w u'', by parts, & show us what you get.
     
  6. Jul 23, 2011 #5
    Yes, I got it. Thanks to both of you.

    Best,
    Niles.
     
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