Step response given impulse response $h = e^{-|t|}$ I was given the above homework problem and I know how the step response is achieved, but I'm not sure how to set up the integrals in order to evaluate the problem. I've attached my work, but it is wrong because I keep getting the wrong answer. The solution is given as

$$S(t) = u(-t)e^t + u(t)(2-e^{-t})$$

*Note: We have not yet covered laplace transform. In my class, we are expressing the step response as running sums/integrals of the impulse response.
HINT: In your work you implicitly assume that $t\ge 0$, so your solution is (probably) correct for $t\ge 0$, but you must also consider the case $t&lt;0$.