If the signal \(x(n)=4 \cos [(\pi / 4) n-(\pi / 6)] u(n)\) is input to the linear system of Exercise 2.6e, determine its steady-state response.

Exercise 2.6e,

(e) \(\frac{1-z^{2}}{\left(2 z^{2}-1\right)(z-2)}\).