Hey guys:

Had one problem with my math homework:

So I tried

So then: ,

So the integration appears as:

Which simplifies to: , which is where I get stuck.

Any advice on moving forward, or a different, easier method?

Peter

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- September 19th 2010, 03:04 PMflybynightIntegration with Trig. Substitution
Hey guys:

Had one problem with my math homework:

So I tried

So then: ,

So the integration appears as:

Which simplifies to: , which is where I get stuck.

Any advice on moving forward, or a different, easier method?

Peter - September 19th 2010, 03:23 PMmr fantastic
- September 19th 2010, 04:56 PMflybynight
Here's what I did:

However, the answer in the textbook (confirmed by Mathematica) is

Any help?

Peter - September 19th 2010, 05:45 PMDefunkt
Your algebra is a bit messy.

First, use linearity to pull out the 1 term from the integral and get

Remembering that and thus you get

Your mistake was that from the first integral to the second (after performing the substitution), you multiplied only the factor by instead of the whole integrand. You also forgot a +25 in the denominator there. - September 19th 2010, 06:04 PMflybynight
Oh I see. I can't believe that I over looked that. Thank you very much!