一阶中立混合型微分方程振动的充分必要条件

NECESSARY AND SUFFICIENT CONDITIONS FOR OSCILLATIONS OF FIRST ORDER NEUTRAL MIXED DELAY EQUATION

本文研究中立混合型微分方程（见（1）式）的振动性．这里所有Pi，qk，ri都是正常数，在文[1]的工作之基础上，我们建立了若干更有效和实用的充要条件．

This paper studies the oscillation of all solutions of the equation where all the coefficients Pi,qk and rj are positive constants. On the basis of the work done by Cheng Wuanji in his,article 'Qscillation Criteria for Higher Order Functional Differential Equation of Mixed Type'some more effective and practical necessary and sufficient conditions are established.