How can I find the Laplace transform of erf without using tables?

janrain
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how do i find the laplace transform of the following error function without using tables?
f(t)=erf(t^(1/2))
i've been trying really long but i seem to be stuck in a loop of erf
 
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janrain said:
how do i find the laplace transform of the following error function without using tables?
f(t)=erf(t^(1/2))
i've been trying really long but i seem to be stuck in a loop of erf

Hey Jarain. Suppose you mean other than Mathematica right?

Just perform the integrations directly then:

\mathcal{L}\left\{\text{Erf}[\sqrt{t}]\right\}=<br /> \int_0^{\infty}e^{-st}\left[\frac{2}{\sqrt{\pi}}\int_0^{\sqrt{t}} e^{-u^2}du\right]dt

Now, can you switch the order of integrations to effect the solution?
 
Last edited:
janrain said:
how do i find the laplace transform of the following error function without using tables?
f(t)=erf(t^(1/2))
i've been trying really long but i seem to be stuck in a loop of erf

Try integrating by parts.
 
Tide said:
Try integrating by parts.

Nice! Thanks.:smile:

Well, then do it both ways Jarain. :rolleyes:

Edit: Oh yea. Tide's way is better.:smile:
 
Hi! I actually just performed this transform recently.
Let dv/dt = \int e^{-st}
Let u = \int_0^{\sqrt{t}} e^{-x^2} dx
 
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