GATE EC 2017 Set 1 Q47 — Control Systems

A linear time invariant (LTI) system with the transfer function 

$$G(s)=\frac{K(s^{2}+2s+2)}{(s_{2}-3s+2)}$$

is connected in unity feedback configuration as shown in the figure.

For the closed loop system shown, the root locus for $0< K < \infty$ intersects the imaginary axis for $K=1.5$. The closed loop system is stable for