Oscillation criteria for certain fourth order nonlinear functional differential equations

Kneser solutions of fourth-order trinomial delay differential equations

“…For a general interest in this field, we refer the reader to [1][2][3][4][5][6][7][8][9][10][11][12][13][14] and the references cited therein. For a general interest in this field, we refer the reader to [1][2][3][4][5][6][7][8][9][10][11][12][13][14] and the references cited therein.…”

“…Even though qualitative properties of solutions of binomial differential equation related to (E), namely, y (4) + q(t)y(τ (t)) = 0 and its various generalizations containing quasi-derivatives have been widely investigated in the literature (see, for example, [1,3,2]), much less is known about asymptotic behavior of (E). So far, prototypes of higher-order trinomial differential equations primarily studied in the literature are such that a difference in the derivative order between the first and the middle term is either one or two.…”

Oscillation theorems for fourth order functional differential equations

“…Much of the literature on the subject has been concerned with equations of the form (1.1) and (1.2) with α = 1 and a(t) = 1 and/or higher order functional differential equations. For typical results, we refer to reader to [1][2][3][4][5][6][7][8][9][10] and the references cited therein. There is however much current interest (see [5][6][7][8]) in the study of the oscillation properties of solutions of (1.1) and (1.2) when α = 1 and ∞ a −1/α (s)ds = ∞.…”

Existence of positive solutions of a third order nonlinear differential equation with positive and negative terms

“…Since Kiguradze's groundbreaking work, there has been a significant growth in the theory of nonautonomous differential equations with deviating argument covering a variety of different problems; see [2][3][4][5][6][7][8][9][10][11][12][13][14] and the references therein.…”