Part 1
%Periodic signal t = 0:0.001:20; x = sin(t); plot(t,x)
%Periodic signal turned non-periodic by setting the sampling period to 0.1 F0 =13; T0 =1/F0; Ts = 0.1; t = 0:Ts:13*T0; x = sin(2*pi*F0*t); plot(t,x)
Part 2
%non-Periodic signal t = 0:0.001:20; x = exp(-t); plot(t,x)
%Made periodic t = 1:0.01:6; for I = 1:1:20 t = t + 6; y1 = exp(-t+I*6); plot(t,y1); hold all end