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

Hi people, I'm really stuck on this, can you please help. Thanks in advance.
http://lmgtfy.com/?q=what+is+the+integral+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).
Reply 2
Avatar for cogito.
cogito.
12
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
(edited 7 years ago)
https://en.wikipedia.org/wiki/List_of_integrals_of_exponential_functions#Other_integrals

More info here: https://www.physicsforums.com/threads/the-integration-of-e-x-2.103752/
(edited 7 years ago)
Reply 4
Avatar for calcumm
calcumm
3
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.
Reply 5
Avatar for cogito.
cogito.
12
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?


Posted from TSR Mobile
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.
(edited 7 years ago)
Reply 7
Avatar for calcumm
calcumm
3
Original post by cogito.
Is this some kind of joke?


Posted from TSR Mobile


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.
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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