Cho tín hiệu: Biến đổi Z của x ( n ) là:

$X\left(Z\right)=\frac{Z}{2-Z}+1+2Z{}^{-1}+4Z{}^{-2}\text{v}�\text{i}\left|Z\right|\le 2\text{v}\text{à}Z\ne 0$

$\text{v}X\left(Z\right)=\frac{Z}{2-Z}+1+2Z{}^{-1}+4Z{}^{-2}\text{v}�\text{i}\left|Z\right|<2\text{v}\text{à}Z\ne 0$

$X\left(Z\right)=\frac{Z}{z-2}+1+2Z{}^{-1}+4Z{}^{-2}\text{v}�\text{i}\left|Z\right|<2\text{v}\text{à}Z\ne 0$

$X\left(Z\right)=\frac{Z}{Z-2}+1+2Z{}^{-1}+4Z{}^{-2}\text{v}�i\left|Z\right|\ge 2\text{v}\text{à}Z\ne 0$