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Integrate not very aggressive about taking constants out of integrals

• To: mathgroup at smc.vnet.net
• Subject: [mg81400] Integrate not very aggressive about taking constants out of integrals
• From: "Darryl Yong" <darrylyong at gmail.com>
• Date: Sat, 22 Sep 2007 03:23:11 -0400 (EDT)

Try the following three few lines of code in Mathematica:

temp1 = Integrate[-Exp[p[s]] , {s,0,t}];
temp2 = Integrate[Exp[p[s]] , {s,0,t}];
temp1+temp2

Out[3] = Integrate[-E^p[s], {s, 0, t}] + Integrate[E^p[s], {s, 0, t}]

FullSimplify[temp1+temp2]

Out[4] = Integrate[-E^p[s], {s, 0, t}] + Integrate[E^p[s], {s, 0, t}]

You'll notice that Mathematica doesn't take the negative sign out of
the integral in temp1, so the result of temp1+temp2 is not zero unless
you define something for p[s] and let it actually work out both
integrals.

Does anyone know of a way to help Mathematica be more aggressive about
taking constants out of integrals?

Thanks, Darryl

• Follow-Ups:
  • Re: Integrate not very aggressive about taking constants out of integrals
    • From: Andrzej Kozlowski <akoz@mimuw.edu.pl>