A problem with an integral
- To: mathgroup at smc.vnet.net
- Subject: [mg32801] A problem with an integral
- From: WhoamI <lushstring at yahoo.com>
- Date: Tue, 12 Feb 2002 06:23:59 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Hi everybody, I have a problem with the next integral
Integrate[Sin[x y],{x,0,1},{y,0,x}]
that after expanding and factoring yields:
\!\(1\/4\ \((EulerGamma - 2\ CosIntegral[1])\)\)
and evaluating this I have -0.024398
To be sure about the answer I taked it other way:
Integrate[
TrigFactor[Integrate[Sin[x y], {y, 0, x}]]
, {x, 0, 1}]
which yields
\!\(1\/2\ \((EulerGamma - CosIntegral[1])\)\)
and evaluating this I have 0.119906
Since I evaluated this integrals not numerically I
don't understand why the answers are different. Is
there something wrong with my code?. I would thanks a
lot for your answers...
Cesar Guerra
Secc. Fisica PUCP-Lima
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