Not enough input arguments

clc
t=2;
f1 = 130;
f2 = 120;
y = 2*cos.*(2*pi*((f1+f2)./2)*t)*cos.*(2*pi*((f1-f2)./2)*t);

Answer 1

[Cameron B]

Is this what you mean?

    y = 2*cos(2*pi*((f1+f2)/2)*t)*cos(2*pi*((f1-f2)/2)*t);