Cauchy-Laurent Series The z-transform is a form of the Cauchy Laurent series and is an analytic function at every point in the roc Let f(z)denote an analytic(or holomorphic) function over an annular region Q centered at z O 8 Re(=) Copyright C 2001, S K MitraCopyright © 2001, S. K. Mitra 8 • The z-transform is a form of the Cauchy￾Laurent series and is an analytic function at every point in the ROC • Let f (z) denote an analytic (or holomorphic) function over an annular region centered at Cauchy-Laurent Series  o z Re( )z Im( )z  o z