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Integral using integral tables

  1. Nov 16, 2004 #1
    Evaluate the integral of x^2 * e^(-2*a*x^2) with respect to x as x ranges from 0 to infinity.

    I can't find anything in the integral tables that match this exactly...Can someone help me out?
  2. jcsd
  3. Nov 16, 2004 #2


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    That looks like a straightforward substitution to me.

    Sorry. misread the integral.. thougt it was 2xe^...

    Try using integration by parts - [itex]x^2 e ^{-2ax^2}=x \times xe^{-2ax^2}[/itex]
    Last edited: Nov 16, 2004
  4. Nov 16, 2004 #3

    Dr Transport

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    integrate by parts or chage variables and let [tex] 2a = b [/tex], I'm sure there is a listing for
    [tex] \int^{\infty} _{0} x^{p} e^{-bx^{2}} dx [/tex].
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