Oscillation of damped PDE with p-Laplacian in unbounded domains

In this paper, new oscillation theorems for the damped partial differential equation (PDE) with p-Laplacian div(A(x) parallel to del u parallel to(p-2)del u) + <(b) over right arrow (x). parallel to del u parallel to(p-2)del u > + c(x)vertical bar u vertical bar(p-2)u = 0 are established in unbounded domains. Our theorems as two special cases when A equivalent to I or A equivalent to I, (b) over right arrow (x) equivalent to 0 improve and complement some existing results in the literature. To illustrate our main results, we give some corollaries and examples. (C) 2009 Elsevier Ltd. All rights reserved.