A=3.7;
tetha=pi/4;
k=[0:31];
length(k)
x=A*cos(tetha*k);
figure(2),stem(k,x)
omega=4*pi;
t=linspace(0,2,100);
y=A*cos(omega*t);
figure(1),plot(t,y)
figure(2),stem(k,x)
teta=pi/8;
%x=A*cos(theta*k);
figure(2),stem(k,x)
a=3;
T=1/32;
alpha=exp(-a*T)
xx=exp(-a*t);
figure(3),plot(t,xx)
k=[0:64];
%yy=alpha^k;
yy=alpha.^k;
figure(4),stem(k,yy)
%xy=x.*y;
length(x)
xy=xx.*y;
figure(5),plot(t,xy)
yyy=yy.*x;
x=A*cos(theta*k);
%yyy=yy.*x;
figure(6),stem(k,yyy)