Question

For non-linear systems stability cannot be determined due to:

(a) Possible existence of multiple equilibrium states

(b) No correspondence between bounded input and bounded output stability and asymptotic stability

(c) Output may be bounded for the particular bounded input but may not be bounded for the bounded inputs

(d) All of the mentioned

I got this question in an interview for job.

Origin of the question is Stability of Nonlinear System in chapter Nonlinear Systems of Control Systems

Answer 1

Correct answer is (d) All of the mentioned

The explanation: For non-linear systems stability cannot be determined as asymptotic stability and BIBO stability concepts cannot be applied, existence of multiple states and unbounded output for many bounded inputs.