Abstract:
We obtain new unimprovable effective conditions for the oscillation of all solutions of linear first-order differential and difference equations with several delays. We show that known results of the kind are consequences of the new results. We reveal the reasons for the impossibility to obtain oscillation conditions for equations with several delays, as sharp as the conditions for the equation with one delay, in case exceptionally known approaches used.
Keywords:differential equation, difference equation, aftereffect, equation with several delays, oscillation, effective conditions.