Asymptotic behavior of a class of nonlinear differential equations of $n$th order

ON THE PERIODIC SOLUTIONS OF A CLASS OF nTH ORDER NONLINEAR DIFFERENTIAL EQUATIONS *

The nth order differential equation x + c (t )x + ƒ( t,x) = e(t),n>3 is considered. Using the Leray-Schauder principle, it is shown that under certain conditions on the functions involved, this equation possesses a periodic solution.

on the periodic solutions of a class of nth order nonlinear differential equations *

the nth order differential equation x + c (t )x + ƒ( t,x) = e(t),n>3 is considered. using the leray-schauder principle, it is shown that under certain conditions on the functions involved, this equation possesses a periodic solution.

Oscillation and Asymptotic Behavior of Solutions of Nth Order Nonlinear Delay Differential Equations*

where n >, 2, a: [0, 00) + [0, a~), q: [0, co) --+ (-00, co), andf: (--co, 03) + (-00, CQ). We assume a(l), q(t), andf( x are continuous, q(t) < t for all t > 0, q(t) 3 co ) as t ---f co, and xf(x) > 0 for x # 0. Usually, a condition of monotonicity on f is needed in order to obtain results for Eq. (1) analogous to those of an ordinary differential equation of the same type. Many authors observ...

Asymptotic Behavior of Positive Solutions of a Class of Systems of Second Order Nonlinear Differential Equations

The two-dimensional system of nonlinear differential equations (A) x′′ = p(t)y, y′′ = q(t)x , with positive exponents α and β satisfying αβ < 1 is analyzed in the framework of regular variation. Under the assumption that p(t) and q(t) are nearly regularly varying it is shown that system (A) may possess three types of positive solutions (x(t), y(t)) which are strongly monotone in the sense that ...

Oscillation and Asymptotic Behavior of Higher-Order Nonlinear Differential Equations