clear all;
t1=0:0.01:10;
f1=3-exp(-t1);
f2=3*exp(-2*t1)+5*5*exp(-t1);
t3=0:0.01:3;
f3=exp(-3*t3).*sin(2*pi*3*t3);
t4=-10:0.1:10;
f4=sin(2*t4)./(2*t4);
figure(1)
subplot(2,2,1),plot(t1,f1)
subplot(2,2,2),plot(t1,f2)
subplot(2,2,3),plot(t3,f3)
subplot(2,2,4),plot(t4,f4)
%%%%%%
syms t
f1='3-exp(-t)';
f2='3*exp(-2*t)+5*5*exp(-t)';
f3='exp(-3*t)*sin(2*pi*3*t)';
f4='sin(2*t)/(2*t)';
figure(2)
subplot(2,2,1),ezplot(f1,[0,10])
subplot(2,2,2),ezplot(f2,[0,10,0,30])
subplot(2,2,3),ezplot(f3,[0,3,-1,1])
subplot(2,2,4),ezplot(f4,[-10,10,-0.5,1])
%%%%%%
syms t
f1='3-exp(-t)';
f2='3*exp(-2*t)+5*5*exp(-t)';
f3='exp(-3*t)*sin(2*pi*3*t)';
f4='sin(2*t)/(2*t)';
t1=0:0.01:10;
f11=subs(f1,t1,t);
f22=subs(f2,t1,t);
t3=0:0.01:3;
f33=subs(f3,t3,t);
f4='sin(2*t)/(2*t)';
t4=-10:0.1:10;
f44=subs(f4,t4,t);
figure(3)
subplot(2,2,1),plot(t1,f11)
subplot(2,2,2),plot(t1,f22)
subplot(2,2,3),plot(t3,f33)
subplot(2,2,4),plot(t4,f44)