z-Transform note: The z-transforms of the two sequences a"un and -a"[-n-1 are identical even though the two parent sequences are different Only way a unique sequence can be associated with a z-transform is by specifying its roc 14 Copyright C 2001, S K MitraCopyright © 2001, S. K. Mitra 14 z-Transform • Note: The z-transforms of the two sequences and are identical even though the two parent sequences are different • Only way a unique sequence can be associated with a z-transform is by specifying its ROC − [−n −1] n [n] n  