The Symbolic Toolbox allows algebraic transformation of a function using the subs command
> Exercise: Variables’ substitution
> Type the following commands, where function is the same as in the previous example.
syms t
y2=subs(f,x,t) %substitutes x with t
y3=subs(f,x,t-1) %substitutes x with t-1
y3=simple(y3) %to simplify the expression for y3
> Exercise: subs Command
> Define function in the Symbolic Toolbox. Make sure that you typed syms x before the function’ definition. Substitute with using subs command. Do not forget to type syms t before substitution.