Previous |  Up |  Next

Article

Keywords:
oscillation; non-oscillation; neutral equation; asymptotic behaviour
Summary:
In this article, we obtain sufficient conditions so that every solution of neutral delay differential equation \[ \big (y(t)- \sum _{i=1}^k p_i(t) y(r_i(t))\big )^{(n)}+ v(t)G( y(g(t)))-u(t)H(y(h(t))) = f(t) \] oscillates or tends to zero as $t\rightarrow \infty $, where, $n \ge 1$ is any positive integer, $p_i$, $r_i\in C^{(n)}([0,\infty ),\mathbb{R})$  and $p_i$ are bounded for each $i=1,2,\dots ,k$. Further, $f\in C([0, \infty ), \mathbb{R})$, $g$, $h$, $v$, $u \in C([0, \infty ), [0, \infty ))$, $G$ and $H \in C(\mathbb{R},\mathbb{R})$. The functional delays $r_i(t)\le t$, $g(t)\le t$ and $h(t)\le t$ and all of them approach $\infty $ as $t\rightarrow \infty $. The results hold when $u\equiv 0$ and $f(t)\equiv 0$. This article extends, generalizes and improves some recent results, and further answers some unanswered questions from the literature.
References:
[1] Dix, J.G., Misra, N., Padhy, L.N., Rath, R.N.: On oscillation and asymptotic behaviour of a neutral differential equations of first order with oscillating coefficients. Electron. J. Qual. Theory Differ. Equ. 19 (2008), 1–10. DOI 10.14232/ejqtde.2008.1.19 | MR 2407546
[2] Gyori, I., Ladas, G.: Oscillation Theory of Delay-Differential Equations with Applications. Clarendon Press, Oxford, 1991. MR 1168471
[3] Hilderbrandt, T.H.: Introduction to the Theory of Integration. Academic Press, New York, 1963. MR 0154957
[4] Karpuz, B., Rath, R.N., Padhy, L.N.: On oscillation and asymptotic behaviour of a higher order neutral differential equation with positive and negative coefficients. Electron. J. Differential Equations 2008 (113) (2008), 1–15, MR2430910. MR 2430910
[5] Ladde, G.S., Lakshmikantham, V., Zhang, B.G.: Oscillation Theory of Differential Equations with Deviating Arguments. Marcel Dekker Inc., New York, 1987. MR 1017244 | Zbl 0832.34071
[6] Parhi, N., Rath, R.N.: On oscillation criteria for a forced neutral differential equation. Bull. Inst. Math. Acad. Sinica 28 (2000), 59–70. MR 1750329
[7] Parhi, N., Rath, R.N.: On oscillation and asymptotic behaviour of solutions of forced first order neutral differential equations. Proceedings of Indian Acad. Sci. Math. Sci., vol. 111, 2001, pp. 337–350. DOI 10.1007/BF02829600 | MR 1851095 | Zbl 0995.34058
[8] Parhi, N., Rath, R.N.: Oscillation criteria for forced first order neutral differential equations with variable coefficients. J. Math. Anal. Appl. 256 (2001), 525–541. DOI 10.1006/jmaa.2000.7315 | MR 1821755 | Zbl 0982.34057
[9] Parhi, N., Rath, R.N.: On oscillation of solutions of forced non linear neutral differential equations of higher order. Czechoslovak Math. J. 53 (2003), 805–825, MR2018832(2005g:34163). DOI 10.1007/s10587-004-0805-8 | MR 2018832
[10] Parhi, N., Rath, R.N.: On oscillation of solutions of forced nonlinear neutral differential equations of higher order II. Ann. Polon. Math. 81 (20033), 101–110. DOI 10.4064/ap81-2-1 | MR 1976190 | Zbl 1037.34058
[11] Parhi, N., Rath, R.N.: Oscillation of solutions of a class of first order neutral differential equations. J. Indian Math. Soc. 71 (2004), 175–188. MR 2290627
[12] Royden, H.L.: Real Analysis. 3rd ed., MacMilan Publ. Co., New York, 1988. MR 1013117 | Zbl 0704.26006
[13] Sahiner, Y., Zafer, A.: Bounded oscillation of non-linear neutral differential equations of arbitrary order. Czechoslovak Math. J. 51 (2001), 185–195. DOI 10.1023/A:1013763409361 | MR 1814644
Partner of
EuDML logo