摘要
Ⅰ. INTRODUCTIONIn studying the stability of a given system by means of the Liapunov function of the special form V(x), a key problem is how to check 【0 or V≤0. We always hope to obtain some necessary and sufficient conditions for 【0 or ≤0 in order to define the largest region of absolute stability. Letov first studied absolute stability of the Lurie system with several nonlinear functions by means of the Liapunov function of the Lurie form V(x). Suffi-
