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From r to R e^(-2r/a)*r^2 dr

  1. Dec 5, 2004 #1
    from r to R e^(-2r/a)*r^2 dr

  2. jcsd
  3. Dec 5, 2004 #2


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    U're one lazy dude... :yuck: Two times part integration,pay attention to signs and integration limits.
  4. Dec 5, 2004 #3


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    Looks pretty standard to me.

    Use "integration by parts", twice.

    If you let u= r2 and dv= e-2r/a, then du= 2r dr and
    v= -a/2 e-2r/a

    Now you have an integral of e-2r/ar and integrating by parts again will give you an integral with just e-2r/a.
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