A system with characteristic equation s4 + 2 s3 + 11 s2 + 18s + 18 = 0 will have closed loop poles such that

No pole lies on the imaginary axis of the s-plane

All poles lie in the left half of the s-plane

All poles lie in the right half of the s-plane

Two poles lie symmetrically on the imaginary axis of the s-plane

A system with characteristic equation s4 + 2 s3 + 11 s2 + 18s + 18 = 0

1.	A system with characteristic equation s4 + 2 s3 + 11 s2 + 18s + 18 = 0 will have closed loop poles such that
A.	All poles lie in the left half of the s-plane
B.	All poles lie in the right half of the s-plane
C.	Two poles lie symmetrically on the imaginary axis of the s-plane
D.	No pole lies on the imaginary axis of the s-plane
Answer» D. No pole lies on the imaginary axis of the s-plane