## Finding definite Integral Help

Limits, differentiation, related rates, integration, trig integrals, etc.
jdom543
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### Finding definite Integral Help

I need to find the definite integral of f(x)=xe^(4x) on the closed interval [-2,2]

I just recently learned how to find definite integrals but most of the ones I've learned weren't like this and are easier at least at first glance (Unless I'm missing something). I know how to use substitution and what not, but I don't see anything here to substitute to make the problem simpler. Thanks

Martingale
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### Re: Finding definite Integral Help

I need to find the definite integral of f(x)=xe^(4x) on the closed interval [-2,2]

I just recently learned how to find definite integrals but most of the ones I've learned weren't like this and are easier at least at first glance (Unless I'm missing something). I know how to use substitution and what not, but I don't see anything here to substitute to make the problem simpler. Thanks
$\int\limits_{-2}^{2}xe^{4x}dx$

use integration by parts

jdom543
Posts: 12
Joined: Tue Dec 01, 2009 3:05 am
Contact:

### Re: Finding definite Integral Help

I need to find the definite integral of f(x)=xe^(4x) on the closed interval [-2,2]

I just recently learned how to find definite integrals but most of the ones I've learned weren't like this and are easier at least at first glance (Unless I'm missing something). I know how to use substitution and what not, but I don't see anything here to substitute to make the problem simpler. Thanks
$\int\limits_{-2}^{2}xe^{4x}dx$

use integration by parts
I haven't learned that yet. At least I don't think I guess I'll google/youtube it for a video on it. Thanks

Martingale
Posts: 333
Joined: Mon Mar 30, 2009 1:30 pm
Location: USA
Contact:

### Re: Finding definite Integral Help

I haven't learned that yet. At least I don't think I guess I'll google/youtube it for a video on it. Thanks
http://www.youtube.com/watch?v=dqaDSlYdRcs

stapel_eliz
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I know how to use substitution and what not....
use integration by parts
I haven't learned that yet.
What methods have you learned?

Thank you!

jdom543
Posts: 12
Joined: Tue Dec 01, 2009 3:05 am
Contact:

### Re:

I know how to use substitution and what not....
use integration by parts
I haven't learned that yet.
What methods have you learned?

Thank you!
The method that I learn usually only involved substitution of one term and then when you decide by the reciprocal derivative of that term it cancels out other terms in the integrand making it much easier to simplify. I've also know about substitution using Trig identities. And now I know Integration by parts since I looked up a video regarding it.

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