On the Qualitative Analysis of Solutions of a Class of Nonlinear Differential Equations of the Second Order with Constant Delay

We consider a class of nonlinear second-order differential equations with constant delay and investigate qualitative properties the solutions, namely, global stability zero solution, eventually uniform boundedness existence periodic unique stationary oscillation considered equations. As far as technique proofs is concerned, we use Lyapunov–Krasovskii functional method second Lyapunov to prove our main results. also improve correct some former results available from literature. Finally, in particular cases, provide three examples illustrations applications obtained new Hence, make contributions topic paper.