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Re: Calculating a simple integral

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• Subject: [mg131081] Re: Calculating a simple integral
• From: "djmpark" <djmpark at comcast.net>
• Date: Mon, 10 Jun 2013 04:11:03 -0400 (EDT)
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Doesn't this have a singularity at 2 Pi that produces non-convergence?  It's
similar to:

Integrate[1/x^2, {x, \[Epsilon], \[Infinity]}, 
 Assumptions -> \[Epsilon] > 0] 

1/\[Epsilon] 

That diverges as epsilon -> 0.

Are you sure you copied the integral correctly?


David Park
djmpark at comcast.net 
http://home.comcast.net/~djmpark/index.html 



From: dsmirnov90 at gmail.com [mailto:dsmirnov90 at gmail.com] 


If there is a way to calculate with Mathematica the following integral:

in = -((-1 + Cos[kz])/(kz^2 (kr^2 + kz^2)^2 (kz^2 - 4 \[Pi]^2)^2))
Integrate[in, {kz, -Infinity, Infinity}, Assumptions -> kr > 0]

Another system calculates the same integral instantly. :)

Thanks for any suggestions.

• Follow-Ups:
  • Re: Calculating a simple integral
    • From: Andrzej Kozlowski <akozlowski@gmail.com>