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Math Help - Error function

  1. #1
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    Error function

    Could anybody know formulation of integration

    f(x)=\int _0 ^x e^{-t^2}dt

    Formulation is not series.
    Last edited by math2009; March 18th 2009 at 04:36 PM.
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  2. #2
    MHF Contributor matheagle's Avatar
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    you cannot integrate this, unless you let x go to infinity.
    However you can approximate it via it's Taylor Series
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  3. #3
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    I try to solve it, and get a approximate formulation

    \int _0 ^x e^{-t^2}dt \approx \frac{\sqrt{\pi (1-e^{-x^2})}}{2}

    There is small error when x < 3
    I believe it must have precision formulation
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  4. #4
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    Quote Originally Posted by math2009 View Post
    I try to solve it, and get a approximate formulation

    \int _0 ^x e^{-t^2}dt \approx \frac{\sqrt{\pi (1-e^{-x^2})}}{2}

    I believe it must have precision formulation
    It doesn't. Read this: Integration of Nonelementary Functions
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  5. #5
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    If k = 1.24 , then
    \int _0 ^x e^{-t^2}dt \approx \frac{\sqrt{\pi (1-e^{-kx^2})}}{2}

    It will approach very small error.
    Could you find k or k(x) to minimum error ?
    If we let limit of error to 0, it mean we get formulation

    As your claim, "There are two things you should never try to prove ...... the impossible and the obvious."
    You never prove it doesn't.
    Attached Thumbnails Attached Thumbnails Error function-s11a.jpg  
    Last edited by math2009; March 18th 2009 at 07:28 PM.
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