Consider the continuous-time system with input xt impulse

Question

Consider the continuous-time system with input x(t), impulse response h(t),and output y(t). Find y(t) by using the formula below

y(t) = x(t) ∗ h(t)

a. x(t) = e^-αt u(t);                          h(t) = e^-βt u(t)

b. x(t) = u(t) - 2u(t - 3) + u(t - 6);   h(t) = e^2tu(1 - t)

c. x(t) = u(t);                                h(t) = δ(t - 3)