Is this two input discrete system linear? [closed]

1. How do you know if a discrete system is linear?
2. What are linear discrete time systems?
3. Which types of discrete time system 2 does not exhibit the necessity of any feedback?

How do you know if a discrete system is linear?

◦ The system is linear. This means that if the input signals x1(t) and x2(t) generate the output signals y1(t) and y2(t), respectively, and if a1 and a2 are constants, then the input signal a1x1(t) + a2x2(t) generates the output signal a1y1(t) + a2y2(t). ◦ The system is time invariant.

What are linear discrete time systems?

A discrete-time linear system is a way of grouping the dynamics of a particular model into a standardized matrix-vector equation. It requires you to separate variables into state (in our case, the position and velocity of the ice block) and controls (the force from the fan).

Which types of discrete time system 2 does not exhibit the necessity of any feedback?

If y(n) depends only on the present and past input, it is called non-recursive. It does not exhibit the necessity of any feedback.