1. The problem statement, all variables and given/known data An electrical network has the unit-impulse response :h(t)=3t⋅e-4t .If a unit voltage step is applied to the network, use the convolution integral to work out the value of the output after 0.25 seconds. 2. Relevant equations Convolution integral: y(t)=f(t)*h(t) Unit step function u(t) = 1 when t>=0, 0 when t<0 3. The attempt at a solution This is a problem on the problem sheet of my circuit analysis course. The lecturer also gives a solution which is not complete: v(τ)=∫∞0 1⋅3(τ-t)e(-4(τ-t)) dt v(0.25) = 4.95×10-2V I'm not sure how to proceed from the above equation to get the final answer. I have tried solving using convolution:y(t) =∫∞0h(τ)u(t-τ)dτ or y(t)=∫∞0u(τ)h(t-τ)dτ,but get something like 0 or -0.192. I guess I dealt with the u(τ) or u(t-τ) in the integral wrong as I'm not sure how to deal with it in an integral. I know that u(t) might affect the limit of the integral but I'm not sure how.(p.s.the∫ part above means integrate from ∞ to 0, if that causes any confusion) Any help or advise would be really appreciated as I've been bothered by this for quite some time.Thanks!