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Re: Inverse Laplace Transform

  • To: mathgroup at smc.vnet.net
  • Subject: [mg108966] Re: Inverse Laplace Transform
  • From: Leslaw Bieniasz <nbbienia at cyf-kr.edu.pl>
  • Date: Thu, 8 Apr 2010 08:03:24 -0400 (EDT)
  • Organization: Academic Computer Center CYFRONET AGH
  • References: <hphq5p$1hm$1@smc.vnet.net>


Hi,

I have reformulated my problem, and now I am getting different terms
in the form:

1/Sqrt[s*(s+a)]/(s-b)

for which the inverse Laplace transform should exist.
However, MATHEMATICA still does not give me the formula for
the inverse. It returns the correct inverse for 1/Sqrt[s*(s+a)],
but not for the above expression, to which it should, in principle,
apply the convolution theorem.

Leslaw



On Wed, 7 Apr 2010, Leslaw Bieniasz wrote:

>
> Hi,
>
> I need to find an inverse Laplace transform of the
> expression:
>
> Sqrt[s*(s+a)]/(s-b)
>
> where "s" is the Laplace variable, "a" is a real positive constant,
> and "b" is a real constant that can be either positive or negative.
> I have tried the InverseLaplaceTransform[] function, but it
> returns the original expression. My question is: does this mean
> that the inverse transform does not exist, or only Mathematica
> cannot find it?
> Also, if anybody knows where I could possibly find the inverse
> in any book, or how I might obtain the inverse otherwise, I would
> appreciate an information. Abramowitz and Stegun book does not have it.
>
> Leslaw
>
>

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