Re: Re: inverting Laplace transforms
- To: mathgroup at smc.vnet.net
- Subject: [mg95168] Re: [mg95132] Re: inverting Laplace transforms
- From: Murray Eisenberg <murray at math.umass.edu>
- Date: Wed, 7 Jan 2009 18:56:23 -0500 (EST)
- Organization: Mathematics & Statistics, Univ. of Mass./Amherst
- References: <gjv78b$p41$1@smc.vnet.net> <200901070911.EAA25449@smc.vnet.net>
- Reply-to: murray at math.umass.edu
Yes, the InverseLaplaceTransform command is available, but when I tried InverseLaplaceTransform[Sqrt[s + a]/(Sqrt[s] (s - b)), s, t] in Mathematica 7.0, after a couple of minutes it just returns the expression unevaluated. Note that, unlike the case with LaplaceTransform, InverseLaplaceTransform does not seem to allow an Assumptions option. Sjoerd C. de Vries wrote: > Dear Leslaw, > > I'll assume you don't have a copy of Mathematica with you, otherwise I > fail to understand why you haven't looked this up yourself in the > excellent electronic documentation. > > Actually, there isn't an excuse at all because it's online as well: > http://reference.wolfram.com/mathematica/guide/Mathematica.html > > Found in 2 seconds: > http://reference.wolfram.com/mathematica/ref/InverseLaplaceTransform.html > > Cheers -- Sjoerd > > > On Jan 6, 11:11 am, Leslaw Bieniasz <nbbie... at cyf-kr.edu.pl> wrote: >> Hello, >> >> I need to invert a few expressions representing Laplace transforms. I hav= > e heard that MATHEMATICA can be used >> for this purpose. Can anybody tell me how to do this? >> >> For example, I need to find a function f(t) for which the >> Laplace transform F(s) is >> >> F(s) = Sqrt[s + a]/(Sqrt[s] * (s - b)) >> >> where a > 0 and b > 0 are constants. >> >> Leslaw > > -- Murray Eisenberg murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 549-1020 (H) University of Massachusetts 413 545-2859 (W) 710 North Pleasant Street fax 413 545-1801 Amherst, MA 01003-9305