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wrong result when computing a definite integral

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  • Subject: [mg129392] wrong result when computing a definite integral
  • From: Dexter Filmore <liquid.phynix at>
  • Date: Thu, 10 Jan 2013 21:39:16 -0500 (EST)
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hi group,

i run into this problem today when giving a bunch of easy integrals to mathematica.
here's a wolfram alpha link to the problem:

the integrand does not depend on the 'x' variable, the inner integration should only result in a factor of 4Pi, and the correct result is a real number, yet the below integral gives a complex number which is far off from the correct value:
Integrate[Exp[I Sqrt[3] y], {x, -2 Pi, 2 Pi}, {y, -Pi, Pi}] -> -((4 I (-1 + E^(2 I Sqrt[3] Pi)) Pi)/Sqrt[3])

from some trial and error it seems the result is also incorrect for non-integer factors in the exponential.

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