Abstract: The oscillation for a class of even order nonlinear variable delay damped functional differential equation with positive and negative coefficients and nonlinear neutral term was discussed. By introducing parameter function and the generalized Riccati transformation, using H¨older inequality and some necessary analytic techniques, some new criteria for the oscillation of the equation were proposed. These criteria improve and generalize some known results. Examples were given to illustrate the main results.

Key words: oscillation, positive and negative coefficient, damped term, functional differential equation, Riccati transformation