I have so much problem in draw nyquist diagram. here is some problem 1-as the book mentioned the open- transfer function doesn't have any pole and zero in right of S plane. and give me the uncompleted diagram so i completed it as you see , but my answer is different form the book !!!! what is my wrong? and other question: 2-here is uncompleted diagrams i completed and solved with this view but one of the answers is wrong .... now what is my problem?!!!! how can i find the best videos references about nyquist in Linear Control System ? Thanks