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 Author Comment/Response Kyung-Taek Lim 10/01/00 08:03am Version Number: 4.0.1.0Platform: Windows 2000 Professional Registered Name: Kyung-Taek_Lim Organization: Brown License ID: L2962-6007 Mathematica gives different results for the same integrals, depending on whether I use x^2-1 or (x-1)(x+1) in the integrand, or depending on the integration variable. In[1]:= Integrate[Sqrt[-(-1/(4x(x^2-1)))],{x,1,infinity}] Out[1]= Sqrt[Pi] Gamma[5/4] / Gamma[3/4] The next cell is the same integral as the above integral, because (x^2-1)=(x-1)(x+1). However, Mathematica produces different result. In[2]:= Integrate[Sqrt[-(-1/(4x(x-1)(x+1)))],{x,1,infinity}] Out[2]= -i EllipticF[ComplexInfinity,2] Now let't perform change of variable. Y=x-1 dY=dx If x=1, Y=0. As x->infinity, Y->infinity. Mathematica produces still different result. In[3]:=Integrate[Sqrt[-(-1/(4(Y+1)(Y)(Y+2)))],{Y,0,infinity}] Out[3]:=0 URL: ,

 Subject (listing for 'different results for the same integrals') Author Date Posted different results for the same integrals Kyung-Taek Lim 10/01/00 08:03am Re: different results for the same integrals Forum Modera... 10/01/00 08:09am
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