Laplace of the following:

L { t ∗ 4δ (t-1) ∗ u(t-2) }

Question

Laplace of the following:

L { t ∗ 4δ (t-1) ∗ u(t-2) }

anonymous · Answer

I know how to do it for 2 functions, but am not sure how to go about it for 3

zzr0ck3r · Answer

why not the definition?

zzr0ck3r · Answer

hmm I forget how to do this, that is the dirac and heaviside functions?

anonymous · Answer

yeah they are the dirac and heaviside.
Can I write$$ L{f(t)*g(t)*h(t)} = F(s)G(s)H(s)$$

zzr0ck3r · Answer

well from - infinity to 2 its going to be 0 right?

zzr0ck3r · Answer

hmm undeifined at 1

anonymous · Answer

I guess so...I don't understand the heaviside or dirac function so well, Sort of just follow the formula

zzr0ck3r · Answer

heaviside u(t-a) is 0 below (a) and 1 above  and dirac(t-b) is infinite at b but the area under the graph is always one

zzr0ck3r · Answer

so i think since its 0 up untill 2 and the dirac will be area 1 at 1 all we have to look at is
int(4t*e^9-st) from 2 to infinity

zzr0ck3r · Answer

hmm maybe not, I have to go to a party man, sorry I cant help more. good luck

anonymous · Answer

np, thanks for trying anyway

anonymous · Answer

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