ON THE ASYMPTOTIC BEHAVIOR OF NONOSCILLATORY SOLUTIONS OF CERTAIN FRACTIONAL DIFFERENTIAL EQUATIONS WITH POSITIVE AND NEGATIVE TERMS

This paper is concerned with the asymptotic behavior of the nonoscillatory solutions of the forced fractional differential equation with positive and negative terms of the form (C)D(c)(alpha)y(t) + f( t, x(t)) = e(t) + k(t)x(eta)(t) + h(t, x(t)), where t >= c >= 1, alpha is an element of (0, 1), eta >= 1 is the ratio of positive odd integers, and (C)D(c)(alpha)y denotes the Caputo fractional derivative of y of order alpha. The cases y(t) = a(t) (x'(t))(eta))' and y(t) = a(t) (x'(t))(eta) are considered. The approach taken here can be applied to other related fractional differential equations. Examples are provided to illustrate the relevance of the results obtained.