Oscillation theorems for second order superlinear differential equations with damping. (English) Zbl 0762.34012

Oscillation criteria are obtained for superlinear differential equations of the type \((rx')'+px'+qf(x)=0\), where \(p,q,r>0\) are real-valued continuous functions in an interval \([a,\infty)\), and \(f:\mathbb{R}\to\mathbb{R}\) is a continuous function satisfying strongly superlinear conditions. The results complement similar earlier ones by M. K. Kwong and J. S. W. Wong [Proc. Am. Math. Soc. 85, 547-551 (1982; Zbl 0503.34022)], Ch. G. Philos [J. Aust. Math. Soc., Ser. A 40, 111-130 (1986; Zbl 0583.34028)] and J. Yan [Proc. Am. Math. Soc. 98, 276-282 (1986; Zbl 0622.34027)].


34C10 Oscillation theory, zeros, disconjugacy and comparison theory for ordinary differential equations