Oscillation Test for Linear Delay Differential Equation with Nonmonotone Argument

Abstract

In this article, we analyze the first order linear delay differential equation \begin{equation*} x^{\prime }(t)+p(t)x\left( \tau (t)\right) =0,\text{ }t\geq t_{0}, \end{equation*} where $p,$ $\tau \in C\left( [t_{0},\infty ),\mathbb{R}^{+}\right) $ and $% \tau (t)\leq t,\ \lim_{t\rightarrow \infty }\tau (t)=\infty $. Under the assumption that $\tau (t)$ is not necessarily monotone, we obtain new sufficient criterion for the oscillatory solutions of this equation. We also give an example illustrating the result.