Draw a Nyquist d·iagram for each of the following systems, and compare the result with that obtained using the MATLAB command Nyquist.

(a)

(b)

(c)

KG(s) = K(s + 1)

s+2 K

KG(s) = (s + 1)(s + 2)2 KG(s) = K(s + 4)(s + 1)

s(s + 2)4 Problem