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    Fun integration problem:

    Integrate e^(x^2)
    and it isn't (e^(x^2))/2x

    any answers?
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    I think.. but I'm not sure, that its 2xe^(x^2)
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    (Original post by Aylia)
    I think.. but I'm not sure, that its 2xe^(x^2)
    If you differentiate that, you get 2e^x^2 + 4x^2.e^(x^2)

    You can't integrate e^(x^2) by methods you've probably learnt (ie. parts and substitution), I'm not even sure how you would do that.
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    sorry that was stupid didn't read the question properly lol
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    http://www.math.ucdavis.edu/~kouba/C...#SOLUTION%2016

    Can't work out if that helps or not...
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    How about Ln?

    y = e^(x^2)
    ln y = x^2 ln e
    ln y = x^2 ( ln e is 1 yes?)
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    (Original post by Aylia)
    How about Ln?

    y = e^(x^2)
    ln y = x^2 ln e
    ln y = x^2 ( ln e is 1 yes?)
    You can't presume Y=f(X).
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    Hm yes, I know you can integrate xe^x^2 using function and derivative, but straight e^x^2, I'll have a think.
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    (Original post by Aylia)
    How about Ln?

    y = e^(x^2)
    ln y = x^2 ln e
    ln y = x^2 ( ln e is 1 yes?)
    That's right, but you could have just missed out that middle line .
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    (Original post by Nylex)
    That's right, but you could have just missed out that middle line .

    yay! have spent ages thinking about that!
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    http://www.nrich.maths.org/discus/me...tml?1078054281
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    are u doing AS Level, P2?, in which case are u sure it wasn't e^(2x). If so the answer would be (1/2)e^(2x).
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    You can't integrate this directly, I'm pretty sure its called the gamma function. Between -infinity and infinity its value is root(2pi).
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    (Original post by Sir I. Newton)
    You can't integrate this directly, I'm pretty sure its called the gamma function. Between -infinity and infinity its value is root(2pi).
    Its not the gamma function,thats gotta do with x!.
    To integrate e^x^2 u have to use a mixture of double integrals and converting from normal integration to polar integration etc etc.
    Its degree level stuff(thats how u integrate the normal distribution function)

    yipee. i remember doing htis a few weeks ago, and i've already forgotten ( :rolleyes: ). something to do with integrating r^x e^r² between 0 and infinity.
 
 
 
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