This paper deals with the second order nonlinear neutral differential inequalities $(A_\nu )$: $(-1)^\nu x(t)\,\lbrace \,z^{\prime \prime }(t)+(-1)^\nu q(t)\,f(x(h(t))) \rbrace \le 0,\ $ $t\ge t_0\ge 0,$ where $\ \nu =0\ $ or $\ \nu =1,\ $ $\ z(t)\,=\,x(t)\,+\,p(t)\,x(t-\tau ),\ $ $\ 0<\tau =\ $ const, $\ p,q,h:[t_0,\infty )\rightarrow R\ $ $\ f:R\rightarrow R\ $ are continuous functions. There are proved sufficient conditions under which every bounded solution of $(A_\nu )$ is either oscillatory or $\ \liminf \limits _{t\rightarrow \infty }|x(t)|=0.$
@article{107521, author = {Myron K. Grammatikopoulos and Pavol Maru\v siak}, title = {Oscillatory properties of solutions of second order nonlinear neutral differential inequalities with oscillating coefficients}, journal = {Archivum Mathematicum}, volume = {031}, year = {1995}, pages = {29-36}, zbl = {0832.34066}, mrnumber = {1342372}, language = {en}, url = {http://dml.mathdoc.fr/item/107521} }
Grammatikopoulos, Myron K.; Marušiak, Pavol. Oscillatory properties of solutions of second order nonlinear neutral differential inequalities with oscillating coefficients. Archivum Mathematicum, Tome 031 (1995) pp. 29-36. http://gdmltest.u-ga.fr/item/107521/
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