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Re: Inverse Laplace Transform

• To: mathgroup at smc.vnet.net
• Subject: [mg108974] Re: Inverse Laplace Transform
• From: dh <dh at metrohm.com>
• Date: Thu, 8 Apr 2010 08:04:54 -0400 (EDT)
• References: <hphq5p$1hm$1@smc.vnet.net>

On 07.04.2010 13:26, 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
>

Hi Leslaw,
a conditions for the existence of the inverse Laplace transform of F[s] is:
Limit[F[s],s->Infinity] == 0
this is not the case for your expression.
cheers, Daniel


-- 

Daniel Huber
Metrohm Ltd.
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