Problem 2: (20 points) Consider the closed-loop system in Figure 2 with
1 Gc(s) = K * Gp(s) * H(s) = 1 / (s^2 + 4s + 6)
1) Sketch the root locus;
(2) With K = 28, the closed-loop system poles are s = 1.37 - j1.39 and 6.20. Hence, for the complex poles, the damping ratio is approximately 0.707. Find the steady-state error for a unit ramp input;
(3) Design a phase-lag compensator that will decrease steady-state error by a factor of 4 such that the closed-loop poles will not be changed significantly;
(4) Find the steady-state error for the compensated system of (3);
(5) Use Matlab to verify the results in (2) - (4).