Re: Problem finding integral of exponentials
- To: mathgroup at smc.vnet.net
- Subject: [mg59640] Re: Problem finding integral of exponentials
- From: "James Gilmore" <james.gilmore at yale.edu>
- Date: Mon, 15 Aug 2005 06:50:32 -0400 (EDT)
- Organization: Yale University
- References: <200508130726.DAA00918@smc.vnet.net> <ddn13u$cv5$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi, Yes I have checked this on my version of Mathematica 5.0, and the integral (Econt) cannot be expressed in any form. Since there is no clear transformation to make on the argument, I think you will have to numerically evaluate the integral for your given constants, or use a series expansion in t to approximately determine the analytic behavior. James Gilmore "Kevin Towles" <kbt22 at drexel.edu> wrote in message news:ddn13u$cv5$1 at smc.vnet.net... > > I have a fairly specific problem of not being able to obtain the > definte integral of a fairly complex function. Does this mean that > this integral is not possible in Mathematica? > > a = AverageDiameter; > r0 = ForsterRadius; > h = BilayerThickness; > R = DomainDiameter; > =CF=84 = DonorLifetime; > > ThisLayer = Integrate[(1 - Exp[(-(t/=CF=84))*(r0/r)^6])*2*Pi*r, > {r,a,TotalR}]; > OtherLayer = Integrate[(1 - Exp[(-(t/=CF=84))*(r0/r)^6])*2*Pi*r, {r, > h,TotalR}]; > pCont = Exp[-(t/=CF=84)]*Exp[(-=CF=83A)*(ThisLayer + OtherLayer)]; > Econt = 1 - (1/=CF=84)*Integrate[pCont, {t, 0, TotalTime}]; > > > All of the variable listed first (a, r0, h, R, and tau) are constants. > > Any help is appreciated, > > Kevin Towles > >
- References:
- Using the VectorCalculus
- From: "Eckhard Schlemm" <e.schlemm@t-online.de>
- Using the VectorCalculus