What is the inverse Laplace of $(e^{-sx/c})(-f_0/s^3)$

Question

Where $c$ and $f_0$ are constants. I know it should be of the form $H(t-a)f(t-a)$ but I got lost a bit

Answer 1

Assuming $f_0,x,c$ are constants and $x,c>0$, Maple says $$ {\rm invlaplace} \left( {\frac {-f_0}{{s}^{3}}{{\rm e}^{-{ sx/c}}}},s,t \right) = -{\frac {f_0\, \left( ct-x \right) ^{2}}{2{c}^{2}} H\left( t-{\frac {x}{c}} \right) } $$ Here $H$ is the Heaviside step function