Solution 3.8.1.6 Applying the Laplace transform, assuming zero initial conditions, yields s 3 Y (s)+5s 2 Y (s)+8sY (s)+6Y (s)=U(s)+sU(s);; or (s 3 +5s 2 +8s +6)Y (s)=U(s)(s +1): Rearranging yields Y (s) U(s) = s +1 s 3 +5s 2 +8s +6 : 1