Without using the Routh-Hur-witz criterion, determine if the following systems are asymptoi'ically stable, marginally stable, or unstable. In each case, the closed-loop transfer .function is given.

(a)

{b)

(c)

{d)

M 8 = 10(s + 2)

( ) s3 + 3s2 + 5s K M(s) = .....,3

,----

s + 5s + 5 100

]\If ( s) = -s3::----2-s72_+_3s_+_1_0 s-1 M(s) = (s + 5)(s2 + 2)

Problem