M2-1(1) t=-2:0.001:4;T=2;xt=rectpuls(t-1,T);plot(t,xt)axis(-2,4,-0.5,1.5)图象为：(2)t=sym(t);y=Heaviside(t);ezplot(y,-1,1);grid onaxis(-1 1 -0.1 1.1)图象为：(3)A=10;a=-1;B=5;b=-2;t=0:0.001:10;xt=A*exp(a*t)-B*exp(b*t);plot(t,xt)图象为：(4)t=sym(t);y=t*Heaviside(t);ezplot(y,-1,3);grid onaxis(-1 3 -0.1 3.1)图象为：(5)A=2;w0=10*pi;phi=pi/6;t=0:0.001:0.5;xt=abs(A*sin(w0*t+phi);plot(t,xt)图象为：(6)A=1;w0=1;B=1;w1=2*pi;t=0:0.001:20;xt=A*cos(w0*t)+B*sin(w1*t);plot(t,xt)图象为：(7)A=4;a=-0.5;w0=2*pi;t=0:0.001:10;xt=A*exp(a*t).*cos(w0*t);plot(t,xt)图象为：(8)w0=30;t=-15:0.001:15;xt=cos(w0*t).*sinc(t/pi);plot(t,xt)axis(-15,15,-1.1,1.1)图象为：M2-3（1） function yt=x2_3(t) yt=(t).*(t=0&t=2&t=3&t=0&t=2&t=3&t0)+0*(t0)+0*(t=0);zi=1 2;y=lsim(sys,x,t,zi)