clc, clear all, close
s = tf('s');
figure(1)
G = (-2*s^2)/(4*s+2);
bode(G), grid on;

figure(2)
G = (-s+1)/(s^2+2*s+1);
bode(G), grid on;

figure(3)
G = (s^2+3*s-2)/(s^2+2*s);
bode(G), grid on;

figure(4)
G = (s^2+3*s-2)/(s^3+s^2);
bode(G), grid on;

figure(5)
G = (s^2-3*s+4)/(s^3+1);
bode(G), grid on;