1. The problem statement, all variables and given/known data What is the inverse laplace transform of (1/(s+s^3))? 2. Relevant equations 3. The attempt at a solution I looked it up on wolframalpha and got 1-cos(t), but I don't understand how they got that answer. I looked up a basic laplace transform chart and didn't see anything that matched; also thought of using partial fractions to simplify it but that didn't work out.