6 papers · 1 filter
A non oscillation criterion for extended quasi linear Hamiltonian systems
G. A. Grigorian
A new approach with the Riccati equation method is used to obtain a non oscillation criterion for extended quasi linear Hamiltonian systems.
Comparison criteria for first order polynomial differential equations
G. A. Grigorian
In this paper we use the comparison method for investigation of first order polynomial differential equations. We prove two comparison criteria for these equations. The proved crit…
On the localization of roots of polynomials
G. A. Grigorian
In this article we use a method of finding the index of a complex-valued function by determined number of arithmetic operations to describe an algorithm of localization of roots of…
Comparison criteria for the Abel equation of 1st kind
G. A. Grigorian
Three comparison criteria for the Abel equation of 1es kind are proved. The results obtained are used to obtain global solvability criteria and some criteria of existence of closed…
Kamenev type conditions for oscillation of third order linear ordinary differential equations
G. A. Grigorian
The Riccati equation method is used to establish Kamenev type conditions for the existence of oscillatory solutions to third order linear ordinary differential equations. Three osc…
Cauchy problem for quasilinear systems of functional differential equations
G. A. Grigorian
We use the contracting mapping principle for proving that under some mild restrictions the Cauchy problem for quasilinear systems of functional differential equations with retarded…