Integral Help: Simplifying Integration with an Arbitrary Constant

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Discussion Overview

The discussion revolves around the integration of the function \(\int \frac { dx } { ( a + x )^2 + \sin^{2} ( \pi x ) }\), where \(a\) is an arbitrary constant. Participants explore the complexity of the integral and share their experiences with various computational tools.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant expresses difficulty in integrating the function, describing it as "ugly" and "nasty."
  • Several participants note that computational tools like Mathematica and Maple indicate that the integral cannot be solved, leading to a sense of uncertainty about its solvability.
  • Another participant mentions that their version of Mathematica can handle a different integral but struggles with the one in question.
  • There is a suggestion to evaluate the integral for specific values of \(x\) where \(\sin(\pi x)\) equals 0 or 1, indicating a potential approach to simplify the problem.
  • One participant humorously remarks on the simplicity of integrating constants, contrasting it with the complexity of the current integral.

Areas of Agreement / Disagreement

Participants generally express uncertainty about the solvability of the integral, with multiple views on the capabilities of computational tools. No consensus is reached regarding a definitive solution or method for integration.

Contextual Notes

Participants reference limitations of computational tools, suggesting that the inability to solve the integral may depend on the specific versions or settings of the software used.

MathNerd
Could someone please help me integrate

[tex]\int \frac { dx } { ( a + x )^2 + sin^{2} ( \pi x ) }[/tex]

where a is just an arbitrary constant...

Thanks in advance...
 
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Oh my. That is ugly.

What kind of evil person is making you do that?

cookiemonster
 
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
 
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Maple 8 says it cannot be done.
No answer I guess.
 
meister said:
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
 
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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
 
Zurtex said:
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
How do you get a sin^2 with no argument?
 
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U can calculate for certain sets of values of x where sin(pi x)=0 or 1
 
Yeah, really. The integral of a constant is a piece of cake.

cookiemonster
 

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