my question is how to creat discrete equations, calculate them and put the created discrete equations in each other such that i get an final diskrete equation
I. y_1(k) = a*y_1(k-1)+b*x_1(k-1)
II. y_2(k) = c*y_2(k-1) + d*y_1(k-1)
Final equation: y_2(k) = c*y_2(k-1) + d*a*y_1(k-2) + d*b*x_1(k-2)
** The values of x_1, i can get from the data set x_1 and for k = 1, y_1(k-1) = 0
** I would like to realize it into "sym".
thank you in advance