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-   -   Inverse Laplace Transform (https://www.mersenneforum.org/showthread.php?t=12986)

 flouran 2010-01-16 00:06

Inverse Laplace Transform

I was looking through some tables of Laplace Transforms on f(t) the other day, and I noticed that in all cases, as [TEX]s \to \infty[/TEX], [TEX]F(s) \to 0[/TEX]. A question that I have been trying to prove is that if [TEX]\lim_{s\to\infty}F(s) = 0[/TEX], then does that necessitate whether [TEX]F(s)[/TEX] can undergo an inverse Laplace transform (i.e. by the Bromwich integral)?

I suspect that the answer is "no", but if anyone has some attempt at a proof I would appreciate it (my idea would be to use Post's inversion formula and utilizing the Grunwald-Letnikov differintegral for evaluating [TEX]F^{(k)}\left(\frac{k}{t}\right)[/TEX], but so far this has been futile).

 flouran 2010-01-18 23:48

[QUOTE=flouran;202052]I was looking through some tables of Laplace Transforms on f(t) the other day, and I noticed that in all cases, as [TEX]s \to \infty[/TEX], [TEX]F(s) \to 0[/TEX]. A question that I have been trying to prove is that if [TEX]\lim_{s\to\infty}F(s) = 0[/TEX], then does that necessitate whether [TEX]F(s)[/TEX] can undergo an inverse Laplace transform (i.e. by the Bromwich integral)?
[/QUOTE]
No.
[QUOTE=flouran;202052]
I suspect that the answer is "no", but if anyone has some attempt at a proof I would appreciate it (my idea would be to use Post's inversion formula and utilizing the Grunwald-Letnikov differintegral for evaluating [TEX]F^{(k)}\left(\frac{k}{t}\right)[/TEX], but so far this has been futile).[/QUOTE]
Well, I managed to finally prove it.

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