MathGroup Archive 2013

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Calculation of a not so simple integral

  • To: mathgroup at smc.vnet.net
  • Subject: [mg131216] Re: Calculation of a not so simple integral
  • From: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>
  • Date: Mon, 17 Jun 2013 06:31:32 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com
  • Delivered-to: l-mathgroup@wolfram.com
  • Delivered-to: mathgroup-outx@smc.vnet.net
  • Delivered-to: mathgroup-newsendx@smc.vnet.net

(*Partial Fractions decomposition,  Fourier Integrals

The problem diagnostics:

Calculate

Integrate[ Sin[x/2]^2 / x^2 / (x^2-4*Pi^2 )^2 / (x^2 + a^2)^2 ,
{x,-oo,oo}, Assumptions-> a>0]

The integrand is nonnegative, has no poles on the real line and decays
rapidly  ~ x^-10 as x->+-oo

Hi, Roland,

I checked your expression, it has a pole on the x axis. Check this

Sin[x/2]^2 / x^2 / (x^2-4*Pi^2 )^2 / (x^2 + a^2)^2//StandardForm

Could it be the case, that you have just written it down in a wrong way?


Alexei BOULBITCH, Dr., habil.
IEE S.A.
ZAE Weiergewan,
11, rue Edmond Reuter,
L-5326 Contern, LUXEMBOURG

Office phone :  +352-2454-2566
Office fax:       +352-2454-3566
mobile phone:  +49 151 52 40 66 44

e-mail: alexei.boulbitch at iee.lu







  • Prev by Date: Re: fit curve on to an imported graph
  • Next by Date: Re: Multiplication by 0: non-zero in versions 8 and 9
  • Previous by thread: Calculation of a not so simple integral
  • Next by thread: Re: Calculation of a not so simple integral