The step function corresponding to the function defined is:
f(t) = e3t + (-e3t+t-1)u(t-1) + (-t+2)u(t-2)
The Laplace Transform is
L(e3t) + e-sL(e3(t+1)+t) + e-2sL(-t) where L is the Laplace transform
The formula used to deal with unit step function was L(u(t-τ)f(t)) = e-sτL(f(t+τ))
Using tables for transform...
1/(s-3) + e-s(e3/(s-3) + 1/s2) + e-2s(-1/s2)
Please go over my math as this calculation is fidgety.
Please consider a tutor. Take care