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International Journal of Engineering & Technology, 7 (4.10) (2018) 793-796
International Journal of Engineering & Technology
Website: www.sciencepubco.com/index.php/IJET
Research paper
Oscillation of Generalized Second-Order Quasi Linear
Difference Equations
V.Srimanju
1
*, Sk.Khadar Babu
2
, V.Chandrasekar
3
1,2
Vellore Institute of Technology, Vellore – 632 014, Tamil Nadu, India
3
Thiruvalluvar University College of Arts and Science, Thennangur - 604 408, Tamil Nadu, India
*Corresponding author E-mail: srimanjushc@gmail.com
Abstract
Authorsipresent sufficienticonditions for theioscillation of the generalizediperturbed quasilinearidifferenceiequation
1
(( 1) ) (( 1) ) (( 1) ) ( ,( )) = ( ,( ), ( )) a x i v x i v x i Fx ivx i Gx ivx i vx i
where 0< <1 , [0, ) x and
x
i x
. Examplesiillustrates the importanceiof our results are alsoiincluded.
Keywords: Generalizedidifference equation; Oscillation; iQuasilinear,
1. Introduction
Difference equations represent captivating mathematical field, has
rich field of the applications in such diverse disciplines as popula-
tion dynamics, operations research, ecology, economics, biology
etc. For thelbackgroundlof differencelequations and its
applicationslin diverselfields withlexamples, see [1]. The study of
difference equations is based on the operator defined as
( )= ( 1) ( ), [0, ). ux ux ux x
Thoughlmany authors [1],[16] have discussed the definition of
as
( )= ( ) ( ), (0, ), ux ux ux (1)
no notable progress have been taken on this line. Butlin [13] the
authors took up the definition of as given in (1), and given
many important results and applications. They labeled the operator
defined by (1) as and its inversely
1
, many interesting
results in number theory were obtained. Qualitativelproperties like
rotatory, expanding, lshrinking, spiral and web like were estab-
lished by extending theory ofl to complex function, for the
solutions of difference equations involving in [2-15, 17-21].
In the sequel, in this paper we will be considered the generalized
perturbed quasi linear difference equation for [0, ) x
1
(( 1) ) (( 1) ) (( 1) ) a x i v x i v x i
( ,( )) = ( ,( ), ( )) Fx ivx i Gx ivx i vx i (2)
where 0< <1 , ( ) ax i is an eventually positive real valued
function, land is the generalized forward difference operator
defined as ( ) = (( 1) ) ( ) vx i v x i vx i .
By alsolution of (2), we mean a nontrivial real valued function
( ) vx i satisfying (2) for [0, ) x . A solution ( ) vx i is said
to be oscillatory if it is neither eventually positive nor negative,
and non oscillatory otherwise.
2. Main Results
In this paper we assume that there exist real valued functions
( ) qx i , ( ) px i andla function : f R R such that
(i). ( )>0 vf v for all 0 v ;
(ii). () ( )= (, )( ) fv fw gvwv w for , 0 vw , where g is a
nonnegativelfunction; land
(iii).
( , )
( )
( )
Fx iv i
qx i
fv i
,
( , , )
( )
( )
Gx iv jw i
px i
fv i
for , 0 vw .
Thelfollowing conditionslare usedlthroughout thislpaper:
1/
1
= ,
(( 1) ) a x i
(3)
1/ 1/
< , < forall >0
() ()
dx dx
fx fx
(4)
0
=
0
inf ( ( ) ( )) 0 for all large ,
lim
x
x
r x
qr i pr i x
(5)
1/ 1/
0 0
< , < for all > 0,
() ()
dx dx
fx fx
(6)