# Instant Notes: 5. Stability Analysis

Completion requirements

A dynamic system is said to be stable if for every bounded input it produces a bounded output, regardless of its initial state.

*Bounded*is an input that always remains between an upper and a lower limit (e.g.: sinusoidal, step, but not the ramp).-
If the transfer function of a dynamic system has even one pole with positive real root, the system is unstable.