The z-Transform rlx(2)=∑a2n=z(rl m=二 ROC=2=relu at which 2(ngr-n< -depends only on r==l, just like the roc in s-plane only depends on Re(s) Last time Unit circle(r=1)in the roc dtfT(e/o)exists rational transforms correspond to signals that are linear combinations of dt exponentialsThe z-Transform • Last time: •Unit circle (r = 1) in the ROC ⇒DTFT X(ejω) exists •Rational transforms correspond to signals that are linear combinations of DT exponentials -depends only on r = |z|, just like the ROC in s-plane only depends on Re(s)