Proof of (2.40)

Dear Thomas Guettinger,

Thank you for your email.
I think the GM-inequality in (2.40) is correct. To derive it
 start from (2.41) which yields
   M_T > |T(jw_180)| = 1/(GM -1 ) (note that we always have GM>1 for stability)
This gives
   (GM-1) > 1/M_T and GM > 1 + 1/M_T QED

Please send me any additional comments.

Best regards,
Sigurd Skogestad
Received on Wed Aug 28 09:25:39 1996