THE DISTRIBUTION OF ZEROES OF SOLUTIONSOF NEUTRAL EQUATIONS

The purpose of ibis paper is to study the distribution of zerocs of solutions of theneutral delay differential equations. An estimate is estublished for the distween betweenadjacenlt zeroes of the solutions of such equations under less restritive hypotheses on the variable coefficients.The results obtained improve and extend scme known resultsin the literature.

An Estimate for Distance Between Adjacent Zeroes of Solutions of Neutral Equations

In this paper, we establish a new estimate for the distance between adjacent zeroes of the solution of the first order neutral differential equation

THE DISTRIBUTION OF ZEROS OF SOLUTIONS OF NEUTRAL DIFFERENTIAL EQUATIONS WITH A VARIABLE DELAY

In this paper, the distribution of zeros of solutions of the first-order neutral differential equation with a variable delayis studied. The estimate for the distance between adjacent zeros of the oscillatory solution of the above equation is obtained.

中立型方程解的零点的分布

本文研究一阶中立型时滞微分方程解的零点的分布，去掉了已有文献中对系数较强的限制条件，获得了这类方程振动解的相邻零点间距离的估计，并且改进和推广了文献中的一些知结果．

中立型时滞微分方程解的零点距估计

考虑中立型时滞微分方程［x（t）＋P（t）x（t－γ）］′＋Q（t）x（t－σ）＝0，其中P（t），Q（t）∈C（［t0，∞），R＋），γ，σ∈R＋．本文对上述方程解的相邻零点间的距离作了新的估计．

具有正负系数的中立型时滞微分方程的零点分布

考虑具有正负系数的中立型时滞微分方程 [x(t)+C(t)x(t-γ))'+P(t)x(t-(?))-Q(t)x(t-σ)=0,其中 .本文给出了上述方程的零点距估计和方程所有解都振动的充分条件,并对一些已有的零点距的估计结果作了改进.