I want to simplify a equation in matlab that has terms of sin(t) and cos(t). When i run it it shows unrecognised variable. What should i do?

This is the code i wrote

Op1("I4")*cos(t)

Here

Op1("I4")=[1 0 0 0; 0 1 0 0;0 0 1 0; 0 0 0 1]

Op1

I want the result to be displayed in terms of cos(t). Please help me out.

Answer 1

[KSSV]

syms t 
Op1 = [1 0 0 0; 0 1 0 0;0 0 1 0; 0 0 0 1] ;
Op1*cos(t)

ans =