Affiliation:
1. Department of Mathematics , Sambalpur University , Sambalpur - 768019 , India
Abstract
Abstract
In this work, sufficient conditions are established for oscillation of all unbounded solutions of a class of fourth order neutral differential equations of the form
(
r
(
t
)
(
y
(
t
)
+
p
(
t
)
y
(
t
−
τ
)
)
″
)
″
+
q
(
t
)
G
(
y
(
t
−
α
)
)
−
h
(
t
)
H
(
y
(
t
−
σ
)
)
=
0
$$\begin{array}{}\displaystyle (r(t)(y(t)+p(t)y(t-\tau))'')''+q(t)G(y(t-\alpha))-h(t)H(y(t-\sigma)) = 0\end{array} $$
under the non-canonical type assumption
∫
0
∞
t
r
(
t
)
d
t
<
∞
$$\begin{array}{}\displaystyle \int\limits_{0}^{\infty}\frac{t}{r(t)}{\rm d} t \lt \infty\end{array} $$
for various ranges of p(t) with ∣p(t)∣ < ∞.
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