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Dono
Posted: Tue Apr 29, 2008 1:56 pm
Guest
I input the following into the web-based Mathematica and it timed out
before giving an answer. Can anyone help finding out if there is a
symbolic answer:

sin[x]*sqrt(1-a*(cos[x])^2*((1+sin[x])^2/(1+a*sin[x])^2+(1-
a)*cos[x]^2))

Please copy and paste the formula in order to avoid introducing
errors. Thank you.
Dono
Posted: Tue Apr 29, 2008 2:02 pm
Guest
Sorry, wrong integrand, here is the correct one:

sin[x]*sqrt(1-a*(cos[x])^2((1+sin[x])^2/(1+a*(sin[x])^2)+(1-
a)*(cos[x])^2))
Eric Gisse
Posted: Tue Apr 29, 2008 3:21 pm
Guest
On Apr 29, 4:02 pm, Dono <sa...@comcast.net> wrote:
Quote:
Sorry, wrong integrand, here is the correct one:

sin[x]*sqrt(1-a*(cos[x])^2((1+sin[x])^2/(1+a*(sin[x])^2)+(1-
a)*(cos[x])^2))

http://img291.imageshack.us/img291/8664/integralvi2.jpg
Dono
Posted: Tue Apr 29, 2008 4:17 pm
Guest
On Apr 29, 6:22 pm, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
Quote:
Mathematica uses Sin[] and Cos[].

Tom Roberts

Dono wrote:
I input the following into the web-based Mathematica and it timed out
before giving an answer. Can anyone help finding out if there is a
symbolic answer:

sin[x]*sqrt(1-a*(cos[x])^2*((1+sin[x])^2/(1+a*sin[x])^2+(1-
a)*cos[x]^2))

Please copy and paste the formula in order to avoid introducing
errors. Thank you.

It recognized the lower case, this is not the problem.
Dono
Posted: Tue Apr 29, 2008 4:18 pm
Guest
On Apr 29, 6:21 pm, Eric Gisse <jowr...@gmail.com> wrote:
Quote:
On Apr 29, 4:02 pm, Dono <sa...@comcast.net> wrote:

Sorry, wrong integrand, here is the correct one:

sin[x]*sqrt(1-a*(cos[x])^2((1+sin[x])^2/(1+a*(sin[x])^2)+(1-
a)*(cos[x])^2))

http://img291.imageshack.us/img291/8664/integralvi2.jpg



Excellent! Thank you , Eric!
Dono
Posted: Tue Apr 29, 2008 6:54 pm
Guest
On Apr 29, 9:42 pm, David W. Cantrell <DWCantr...@sigmaxi.net> wrote:
Quote:
Dono <sa...@comcast.net> wrote:
On Apr 29, 6:21 pm, Eric Gisse <jowr...@gmail.com> wrote:
On Apr 29, 4:02 pm, Dono <sa...@comcast.net> wrote:

Sorry, wrong integrand, here is the correct one:

sin[x]*sqrt(1-a*(cos[x])^2((1+sin[x])^2/(1+a*(sin[x])^2)+(1-
a)*(cos[x])^2))

http://img291.imageshack.us/img291/8664/integralvi2.jpg

Excellent! Thank you , Eric!

Your jubilation is, I think, premature. If you differentiate the supposed
antiderivative shown there, you get just

sin(x) sqrt(1 - a cos(x)^2)

which is not equal to the given integrand.

David



Hmm,

So, what is the correct answer?
Eric Gisse
Posted: Tue Apr 29, 2008 7:38 pm
Guest
On Apr 29, 8:42 pm, David W. Cantrell <DWCantr...@sigmaxi.net> wrote:
Quote:
Dono <sa...@comcast.net> wrote:
On Apr 29, 6:21 pm, Eric Gisse <jowr...@gmail.com> wrote:
On Apr 29, 4:02 pm, Dono <sa...@comcast.net> wrote:

Sorry, wrong integrand, here is the correct one:

sin[x]*sqrt(1-a*(cos[x])^2((1+sin[x])^2/(1+a*(sin[x])^2)+(1-
a)*(cos[x])^2))

http://img291.imageshack.us/img291/8664/integralvi2.jpg

Excellent! Thank you , Eric!

Your jubilation is, I think, premature. If you differentiate the supposed
antiderivative shown there, you get just

sin(x) sqrt(1 - a cos(x)^2)

which is not equal to the given integrand.

Yes, it is. If you have Maple, Mathematica, or MATLAB, have one of
them [preferably Maple] apply the relevant simplify command to the
expression.

Quote:

David
Tom Roberts
Posted: Tue Apr 29, 2008 8:22 pm
Guest
Mathematica uses Sin[] and Cos[].

Tom Roberts


Dono wrote:
Quote:
I input the following into the web-based Mathematica and it timed out
before giving an answer. Can anyone help finding out if there is a
symbolic answer:

sin[x]*sqrt(1-a*(cos[x])^2*((1+sin[x])^2/(1+a*sin[x])^2+(1-
a)*cos[x]^2))

Please copy and paste the formula in order to avoid introducing
errors. Thank you.
David W. Cantrell
Posted: Tue Apr 29, 2008 11:42 pm
Guest
Dono <sa_ge@comcast.net> wrote:
Quote:
On Apr 29, 6:21 pm, Eric Gisse <jowr...@gmail.com> wrote:
On Apr 29, 4:02 pm, Dono <sa...@comcast.net> wrote:

Sorry, wrong integrand, here is the correct one:

sin[x]*sqrt(1-a*(cos[x])^2((1+sin[x])^2/(1+a*(sin[x])^2)+(1-
a)*(cos[x])^2))

http://img291.imageshack.us/img291/8664/integralvi2.jpg

Excellent! Thank you , Eric!

Your jubilation is, I think, premature. If you differentiate the supposed
antiderivative shown there, you get just

sin(x) sqrt(1 - a cos(x)^2)

which is not equal to the given integrand.

David
 
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