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What is the integral of e to the power of x squared, and why? Please help! Watch

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    Hi people, I'm really stuck on this, can you please help. Thanks in advance.
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    http://lmgtfy.com/?q=what+is+the+int...of+e%5E(x%5E2)

    Alternatively, put it into an integral calculator. You'll see that it's way beyond any a-level spec, so you don't need to know it.

    You need some sort of kx before the e^(x^2) for it to form a standard integral. f'(x)e^f(x).
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    First you need to know erf function, and I suppose you won't ask this if you already know what erf is.

    A substitution dx dy = r dr d(theta) might help
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    https://en.wikipedia.org/wiki/List_o...ther_integrals

    More info here: https://www.physicsforums.com/thread...-e-x-2.103752/
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    1/2x e^x^2

    Think of it this way;

    What coefficient of e do I need to have so that when I derive it I get e^x^2 on it's own.
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    (Original post by calcumm)
    1/2x e^x^2

    Think of it this way;

    What coefficient of e do I need to have so that when I derive it I get e^x^2 on it's own.
    Is this some kind of joke?


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    (Original post by calcumm)
    1/2x e^x^2

    Think of it this way;

    What coefficient of e do I need to have so that when I derive it I get e^x^2 on it's own.
    No, that is wrong.

    If we use a substitution u=x^2 we get du=2x dx

    So ∫ e^(x^2) dx = ∫ e^u 1/(2√u) du which isn't helpful.
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    (Original post by cogito.)
    Is this some kind of joke?


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    (Original post by Math12345)
    No, that is wrong.

    If we use a substitution u=x^2 we get du=2x dx

    So ∫ e^(x^2) dx = ∫ e^u 1/(2√u) du which isn't helpful.


    Oh my god, brb, dropping A level maths.
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    (Original post by calcumm)
    Oh my god, brb, dropping A level maths.
    Think you are confusing differentiation and integration. Integration is usually harder.
 
 
 
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