Lyapunov-Krasovsky Functionals and the Existence of Unbounded Solutions of Functional-Differential Equations of Retarded Type

In this paper, the concepts of unboundedness and partial unboundedness of solutions of functional-differential equations of retarded type are introduced. On the basis of the method of Lyapunov-Krasovsky functionals, sufficient conditions for the existence of partially unbounded solutions are obtained. As corollaries, sufficient conditions for the existence of unbounded solutions are obtained.