The z-transform of the sequence x(n) is given by
Eq. (6.76) gives the expansion in power series form. From power series we get the following sequence:
It is possible to get the power series expansion directly or by long division. In power series expansion technique ROC has a vital role.
Example 6.9 Determine the inverse Z-transform of by long division method when (a) ROC: | z | > 1 and (b) ROC: respectively.