If a feedback control system has its open loop transfer function G(s)H(s) = K/(s-2)(s^2+3s+5) has the root locus plot which intersects the imaginary axis at s =0, then the value of K at this point will be
(a) -5
(b) 10
(c) 5
(d) -10
I have been asked this question in homework.
My question comes from Construction of Root Loci in division The Root Locus Technique of Control Systems