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QM Integral and Online Integral Tables

  1. Jan 17, 2005 #1
    Hello, I am hung up on an integral from Quantum Mechanics. I searched on Yahoo and Google for online integral tables, but failed to discover anything beyond very basic tables. The integral is as follows:

    [tex] \int_{-\infty}^{\infty} \(A*e^{-(x-a)^2} dx [/tex]

    Are there any decent online integral tables that are accessible to just anyone? I found some online databases but quickly found out that I had to subscribe.

    Thank You,
    Last edited: Jan 17, 2005
  2. jcsd
  3. Jan 17, 2005 #2


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    Is A just a constant or a matrix?
  4. Jan 17, 2005 #3


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    The appropriate question would have bee:is A "x" dependent or not????

  5. Jan 17, 2005 #4
    Oops, sorry, A is a constant. It is not dependent upon x. I could have just left that out.
  6. Jan 17, 2005 #5


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    In that case,it can be reduced (by a simple substitution) to a Poisson integral which is doable appling the thoerem of Fubini and polar plane coordinates...

  7. Jan 17, 2005 #6
    What he means is, square the integral and transform to polar coordinates, then use u-substitution (inverse chain rule) to solve an easy integral, take the square root of the result.

    As a side note, it is impossible to find an antiderivative for your integral. No antiderivative exits (in terms of familiar functions).

    As a side-side note, if a = 0 and A = 1, the answer is sqrt(pi)
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