Our aim in this paper is to present criteria for oscillation of the nonlinear differential equation $$u^{\text{'}\text{'}}\left(t\right)+p\left(t\right)f\left(u\left(g\left(t\right)\right)\right)=0.$$ The obtained oscillatory criteria improve existing ones.

By means of Riccati transformation technique, we establish some new oscillation criteria for third-order nonlinear delay dynamic equations ${\left({\left(x^{\Delta \Delta }\left(t\right)\right)}^{\gamma }\right)}^{\Delta }+p\left(t\right)x^{\gamma }\left(\tau \left(t\right)\right)=0$ on a time scale ; here γ > 0 is a quotient of odd positive integers and p a real-valued positive rd-continuous function defined on . Our results not only extend and improve the results of T. S. Hassan [Math. Comput. Modelling 49 (2009)] but also unify the results on oscillation of third-order delay differential equations and third-order delay difference...

In this work, necessary and sufficient conditions for the oscillation of solutions of 2-dimensional linear neutral delay difference systems of the form $$\Delta \left[\begin{array}{c}x\left(n\right)+p\left(n\right)x(n-m)\\ y\left(n\right)+p\left(n\right)y(n-m)\end{array}\right]=\left[\begin{array}{cc}a\left(n\right)& b\left(n\right)\\ c\left(n\right)& d\left(n\right)\end{array}\right]\left[\begin{array}{c}x(n-\alpha )\\ y(n-\beta )\end{array}\right]$$ are established, where $m>0$, $\alpha \ge 0$, $\beta \ge 0$ are integers and $a\left(n\right)$, $b\left(n\right)$, $c\left(n\right)$, $d\left(n\right)$, $p\left(n\right)$ are sequences of real numbers.

2000 Mathematics Subject Classification: 39A10.The oscillatory and nonoscillatory behaviour of solutions of the second order quasi linear neutral delay difference equation Δ(an | Δ(xn+pnxn-τ)|α-1 Δ(xn+pnxn-τ) + qnf(xn-σ)g(Δxn) = 0 where n ∈ N(n0), α > 0, τ, σ are fixed non negative integers, {an}, {pn}, {qn} are real sequences and f and g real valued continuous functions are studied. Our results generalize and improve some known results of neutral delay difference equations.