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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- Jun 25th 2010, 11:45 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

- Jun 25th 2010, 12:06 PMAckbeet
Hmm. I don't get your result. Could you please post a few more steps?

- Jun 25th 2010, 12:36 PMMechEng
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? - Jun 25th 2010, 12:37 PMAlso 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?) - Jun 25th 2010, 12:38 PMAckbeet
Double-check your denominator.

- Jun 25th 2010, 12:45 PMslider142
- Jun 25th 2010, 12:47 PMTheCoffeeMachine
- Jun 25th 2010, 12:47 PMAlso sprach Zarathustrano,
it's:

- Jun 25th 2010, 12:53 PMTheCoffeeMachine
- Jun 25th 2010, 01:08 PMAlso sprach Zarathustra
You are blind or what??? Where are you see minus??? hahaha...

- Jun 29th 2010, 12:15 PMMechEng
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? - Jun 29th 2010, 12:37 PMTheCoffeeMachine
- Jun 29th 2010, 12:58 PMMechEng
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. - Jun 29th 2010, 01:15 PMskeeter
note the identity ...

sub in for in the integrand ...

back substitute ...

- Jun 29th 2010, 01:27 PMMechEng