Good afternoon,

I have worked out the following problem and arrived at the following answer. Would someone mind verifying this for me?

let

let

I arrive at

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- June 25th 2010, 10:45 AMMechEngtrig substitution
Good afternoon,

I have worked out the following problem and arrived at the following answer. Would someone mind verifying this for me?

let

let

I arrive at

- June 25th 2010, 11:06 AMAckbeet
Hmm. I don't get your result. Could you please post a few more steps?

- June 25th 2010, 11:36 AMMechEng
Sure,

Using the substition...

I get...

So...

Wait... Should that have been...

This must have been where I went wrong. What should this have been, and why? - June 25th 2010, 11:37 AMAlso sprach Zarathustra
[QUOTE=MechEng;530685]Good afternoon,

I have worked out the following problem and arrived at the following answer. Would someone mind verifying this for me?

let

let

The substitution is good!!!

...but the final answer is wrong!

(Take the derivative of what you got, is it the integrand?) - June 25th 2010, 11:38 AMAckbeet
Double-check your denominator.

- June 25th 2010, 11:45 AMslider142
- June 25th 2010, 11:47 AMTheCoffeeMachine
- June 25th 2010, 11:47 AMAlso sprach Zarathustrano,
it's:

- June 25th 2010, 11:53 AMTheCoffeeMachine
- June 25th 2010, 12:08 PMAlso sprach Zarathustra
You are blind or what??? Where are you see minus??? hahaha...

- June 29th 2010, 11:15 AMMechEng
Good afternoon All,

I am sitting at work without my notes today, trying to pickup where I left off on this one.

Using the "correct" substitution I get the following:

Can this be reduced to:

And then:

And then:

Since we have and

So:

And:

Am I totally off target again? - June 29th 2010, 11:37 AMTheCoffeeMachine
- June 29th 2010, 11:58 AMMechEng
Should that look more like:

=

I guess I'm confused by the . Well, that and I am trying to do this without notes of any kind... between phone calls and e-mails.

Thank you. - June 29th 2010, 12:15 PMskeeter
note the identity ...

sub in for in the integrand ...

back substitute ...

- June 29th 2010, 12:27 PMMechEng