clear;
t=-1:0.01:6;
t1=0.02;
f=2*t.*(u(t)-u(t-1))+2*(u(t-1)-u(t-4))-2*(t-5).*(u(t-4)-u(t-5));
f1=2*(u(t)-u(t-1))-2*(u(t-4)-u(t-5));
f2=t.^2.*(u(t)-u(t-1))+(2*(t-1)+1).*(u(t-1)-u(t-4))+(-((t-5).^2)+1+7).*(u(t-4)-u(t-5))+8*u(t-5);
Subplot(221)
plot(t,f,'r');grid on;title('The original signal f(t)');
Subplot(222)
plot(t,f1,'r');grid on;title('The derivative of signal f(t)');
Subplot(223)
plot(t,f2,'r');grid on;title('The integration of signal f(t)');