New oscillation theorems for a class of second-order damped nonlinear differential equations

Abstract

Some new oscillation criteria are established for the nonlinear damped differential equation $${\left( {r\left( t \right){k_1}\left( {x,x'} \right)} \right)^\prime } + p\left( t \right){k_2}\left( {x,x'} \right)x' + q\left( t \right)f\left( {x\left( t \right)} \right) = 0,\;t \ge {t_0}.$$ The results obtained extend and improve some existing results.