MATLAB: How do i multiply two functions

functions

Hello, i have an assignment for school in which i need to plot the z function, where z needs to be:
z=x1*x2,
x1=29*t^2-165*t+420
x2=x2=symsum((-1)^k*dirac(t-24*k), k, -100, 100),
and t=0:1:24*25 (to represent 25 periods of x2).
But when i try to multiply x1 with x2, i get this error:
Error using symengine, The dimensions do not match.
What can i do?

Best Answer

Try this:
syms t k
x1=29*t^2-165*t+420 
x2=symsum((-1)^k*dirac(t-24*k), k, -100, 100)
tt=subs(t,0:1:24*25);
x1=subs(x1,t,tt)
x2=subs(x2,t,tt)
z=x1.*x2;
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