% Model-based control systems
% Exercise 12
clearvars
close all
clc
%%
s=tf('s');
T=(40*s+80)/((s+4)*(s^2+4*s+28));

figure(1);clf;
bodemag(T)
hold on 
yline(6,'--','DisplayName','1/|\Delta_{fi}|')
grid on; grid minor;
legend('Location','southwest');

x = hinfnorm(T)