Use z transforms to find the ZIR yZI(k), the ZSR yZS(k), and the complete response y(k) for each system.
(E+0.5){y(k)} = 0, y(0) = 0.
(E2-3E+2){y(k)} = us(k), y(0) = 2, y(1) = 0. (us(k) = unit step sequence.)
(E2-2E+2){y(k)} = (2)-kus(k), y(0) = y(1) = 0.