inverse laplace 1/(s*exp(3*s))
The factor e-3s delays the original function by 3: invert 1s, then replace t with t -3
Find the causal inverse transform, for t ≥ 0. By linearity, invert each partial fraction
The inverse Laplace formula for 1(s -a)n is tn -1·exp(at)(n -1)!; it gives for 1s: exp(0·t)0!
⇥ⓘ A product with a zero factor is zero: 0·t = 0■Any nonzero number raised to the power 0 is 1: exp(0) = 1■By convention, the factorial of 0 is 1: 0! = 1
⇥ 11
⇥ 1
Delayed by 3, the original function is zero for t < 3: replace t with t -3 and multiply by the unit step u(t -3), which is 0 for t < 3 and 1 for t ≥ 3:
▶Inverse Laplace transform:   u(t -3)