On the Instability of Solutions of Certain Fifth Order Nonlinear Differential Equations

Abstract

The main purpose of this paper is to give sufficient conditions which guarantee the instability of the trivial solution of a nonlinear vector differential equation as follows: X-(5) + psi((X) over dot,<(X)double over dot>)(X) triple over dot + (phi)(X,(X) over dot ,<(X)double over dot>) + circle minus(X) over dot + F(X) 0.