Ex.3.2 Left-sided exponential sequence Determine the z-transform,including the ROC pole-zero-plot,for sequence: xn=-a"u-n-1] Solution: X(2)-∑4-n-2"=-∑d'z" 1-a1z z-0 Condition of convergence: Zero∶z= Roc:a'z<1,a pole:z=a 1616 Ex. 3.2 Left-sided exponential sequence ( )   1 1 n n n n n n X z a z u n a z  − − =− − =− =− −   − − = xn= −a u− n −1 n z a ( ) 1 1 1 n n n n n a z a z  −  − = = =− =−   ◆Determine the z-transform, including the ROC, pole-zero-plot, for sequence: Solution: ROC: z z a = − : 0 : zero z pole z a = = ( ) 1 1 1 1 a z a z a z − −  − − =− − 0 -1 a z1, Condition of convergence: