Show that if TN (i.e., the N -th iterate of T) has an unique xed point for some N , then T also has an unique xed point. (This result shows that if the N th iterate of T is contractive, then all our dynamic programming results based on contraction of T carry over. This is very useful in the study of many systems such as queueing networks, where T itself may not be contractive, but one can nd an iterate of it that is however contractive)