help with integration by parts

[kenshintomoe225]

okay so i am not very good at calculus, but it is required by my major. i currently have a homework problem to do that is integration by parts and i am not sure if i am right. any help would be greatly appreciated!!!



the problem is to integrate

x^2*e^-x^2 dx using integration by seperation


the answer i got was (-x^4 * e^-x^2 - e^-x^2((-x^4)/2) + C)

i beg for any help on this problem!!

 

[stapel]

Where are you needing help?

If you're not sure of your integration, then differentiate: if you get what you started with, then you integrated correctly.

If you have some other question, please reply with clarification, and please include a full listing of your steps and reasoning. Thank you.

Eliz.

 

[kenshintomoe225]

this problem

well like i said i am not very good at calculus and i just want a second opinion

(x^2)*(e^-(x^2)) dx is the problem

if someone could please work it and explain it to me i would appreciate it, just to make sure i am doing it right.

thank you

 

[tkhunny]

I'd think about splitting it up like this:

x*[x*(e^-(x^2))]

That should give you a clue how to proceed.

If not, maybe this version:

-½x*[-2x*(e^-(x^2))]

Still, I don't see how that is going to come out as you have stated. The derivative of the supposed answer is not all that close to the integrand, as presented. How sure are you that we have the right problem?