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

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

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

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

1. $K>1.5$
2. $1<K<1.5$
3. $0<K<1$
4. no positive value of $K$

recategorized