c1 = conv([1 3], [1 20]);
c = conv([1 0],c1);
%L0 = tf(1,c);
%rlocus(L0);
%title('Problem 5a: Root-locus for G_c = H = 1');
%text(-30,10,'Stable for K < 1380');


% L0 = tf([1 4],c);
% rlocus(L0);
% title('Problem 5bc: Root-locus when G_c*H = (s+4)');
% K = 200;
% R = rlocus(L0,K);

Gc = [1 4];
H = [1];
K = 200;

CR = tf(K*Gc,c+[0 0 K*conv(Gc,H)]);
subplot(211);
step(CR);
title('Problem 5b: Step reponse of Gc(s)=s+4, H=1');

Gc = [1];
H = [1 4];

CR2 = tf(K*Gc,c+[0 0 K*conv(Gc,H)]);
subplot(212);
step(CR2);
title('Problem 5c: Step response of Gc=1, H(s)=s+4');
