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MathNerd
Apr2-04, 10:28 PM
Could someone please help me integrate

\int \frac { dx } { ( a + x )^2 + sin^{2} ( \pi x ) }

where a is just an arbitrary constant...

Thanks in advance...

cookiemonster
Apr2-04, 10:32 PM
Oh my. That is ugly.

What kind of evil person is making you do that?

cookiemonster

meister
Apr3-04, 05:08 AM
The Integrator can't do it, therefore it's impossible. (I know this isn't true, but when Mathematica can't do it I get kind of scared.)

http://integrals.wolfram.com/index.en.cgi

It just spits this out: http://integrals.wolfram.com/graphics.cgi?format=StandardForm&FontSize=Medium&expr=1/Sqrt%5B%28a%2Bx%29%5E2%20%2B%20%28Sin%5BPi%2Ax%5D% 29%5E2%5D

ShawnD
Apr3-04, 06:30 AM
Maple 8 says it cannot be done.
No answer I guess.

Zurtex
Apr3-04, 11:02 AM
The Integrator can't do it, therefore it's impossible. (I know this isn't true, but when Mathematica can't do it I get kind of scared.)

I can never get that to do a difficult integration when I have one. But yes this does look like a really nasty one.

Edit: I put it in and got this: http://integrals.wolfram.com/graphics.cgi?format=StandardForm&FontSize=Medium&x=24&expr=1%20/%20%28%20%28a%20%2B%20x%29%5E2%20%2B%20sin%5E2%28% 28Pi%29x%29%20%29&y=21

cookiemonster
Apr3-04, 03:59 PM
Both my version of Mathematica and the Integrator return the integral.

The first one you had, MathNerd, Mathematica could do, but this new one doesn't work out.

cookiemonster

meister
Apr4-04, 12:17 AM
I can never get that to do a difficult integration when I have one. But yes this does look like a really nasty one.

Edit: I put it in and got this: http://integrals.wolfram.com/graphics.cgi?format=StandardForm&FontSize=Medium&x=24&expr=1%20/%20%28%20%28a%20%2B%20x%29%5E2%20%2B%20sin%5E2%28% 28Pi%29x%29%20%29&y=21How do you get a sin^2 with no argument?

himanshu121
Apr4-04, 12:43 AM
U can calculate for certain sets of values of x where sin(pi x)=0 or 1

cookiemonster
Apr4-04, 01:12 AM
Yeah, really. The integral of a constant is a piece of cake.

cookiemonster