MathGroup Archive 2007

[Date Index] [Thread Index] [Author Index]

Search the Archive

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


  • Prev by Date: Boundary problems
  • Next by Date: Error using Notebook?
  • Previous by thread: Re: Boundary problems
  • Next by thread: Re: Integrate not very aggressive about taking constants out of integrals