q Let P = NM-1 be normalized right coprime factorization.
Then
•
• small l(P) Þ small bopt(P)
• Let the open right-half
plane zeros and poles of P be:
• z1, z2,…, zm, p1, p2,…, pk
• Define
•
• Then P(s)=P0(s)Nz(s)/Np(s)
• where P0(s) has no open right-half plane zeros and poles.