Abstract
This paper is devoted to study some nonlinear elliptic Neumann equations of the type
{
A
u
+
g
(
x
,
u
,
∇
u
)
+
|
u
|
q
(
⋅
)
-
2
u
=
f
(
x
,
u
,
∇
u
)
in
Ω
,
∑
i
=
1
N
a
i
(
x
,
u
,
∇
u
)
⋅
n
i
=
0
on
∂
Ω
,
\left\{ {\matrix{ {Au + g(x,u,\nabla u) + |u{|^{q( \cdot ) - 2}}u = f(x,u,\nabla u)} \hfill & {{\rm{in}}} \hfill & {\Omega ,} \hfill \cr {\sum\limits_{i = 1}^N {{a_i}(x,u,\nabla u) \cdot {n_i} = 0} } \hfill & {{\rm{on}}} \hfill & {\partial \Omega ,} \hfill \cr } } \right.
in the anisotropic variable exponent Sobolev spaces, where A is a Leray-Lions operator and g(x, u, ∇u), f (x, u, ∇u) are two Carathéodory functions that verify some growth conditions. We prove the existence of renormalized solutions for our strongly nonlinear elliptic Neumann problem.