| LYAPUNOV's INEQUALITY FOR LINEAR DIFFERENTIAL ALGEBRAIC EQUATION Nguyen Dinh Cong and Hoang Nam Abstract We introduce a concept of Lyapunov exponents and Lyapunov spectrum of a linear differential algebraic equation (DAE) and derive Lyapunov's inequality for a DAE of index 1. We derive some estimates for sum of Lyapunov exponents from a fundamental solution matrix of a DAE by means of its coefficients. |