On nondecreasing singular solutions of the Emden-Fowler equation.
The paper deals with oscillation criteria of fourth order linear differential equations with quasi-derivatives.
Sufficient conditions are obtained in terms of coefficient functions such that a linear homogeneous third order differential equation is strongly oscillatory.
The differential equation of the form , a ∈ (0,∞), is considered and solutions u with u(0) = 0 and (u(t))² + (u’(t))² > 0 on (0,∞) are studied. Theorems about existence, uniqueness, boundedness and dependence of solutions on a parameter are given.
Integral criteria are established for and , where is the space of solutions of the equation satisfying the condition