Integration Bug
- To: mathgroup at smc.vnet.net
- Subject: [mg65236] Integration Bug
- From: "Chris H. Fleming" <chris_h_fleming at yahoo.com>
- Date: Sun, 19 Mar 2006 03:19:14 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
I am finding some weird bugs when Mathematica integrates
EXP*TRIG/Polynomial to infinity.
$Assumptions = {0 < t, 0 < Ï?, 0 < γ< Ω};
Ï?1 = +Ω + i γ;
Ï?2 = +Ω - i γ;
Ï?3 = -Ω + i γ;
Ï?4 = -Ω - i γ;
this integral is correct
Integrate[Ï? Cos[Ï? t] /
((Ï?-Ï?1)(Ï?-Ï?1)(Ï?-Ï?1)(Ï?-Ï?1)),{Ï?,0,Infinity}] //FullSimplify
Although the answer it gives is correct, I want answers in Ei form and
not Ci and Si
so I substituted Cos[x] for 1/2(Exp[i x]+Exp[-i x])
Integrate[Ï? (Exp[i Ï? t]+Exp[-i Ï? t])/2 /
((Ï?-Ï?1)(Ï?-Ï?1)(Ï?-Ï?1)(Ï?-Ï?1)),{Ï?,0,Infinity}] //FullSimplify
and this answer is in the form of Ei, but it is completely wrong
similar things happen with other integrals of this kind. Fortunately I
know how to do these by hand.