ON THE OSCILLATION OF AN ELLIPTIC EQUATION OF FOURTH ORDER
Main Article Content
Abstract
The elliptic equation
\[\Delta^2 u(|x|)+g(|x|)u(|x|)=f(|x|)\]
is studied for its oscillatory behavior. $\Delta$ is the Laplace operator. Sufficient condi tions have been found to ensure that all solutions of this equation continuable in some exterior domain $\Omega=\{x=(x_1, x_2, x_3):|x|>A\}$ where $|x|=(\sum_{i=1}^3 x_i^2)^{1/2}$ are oscillatory.
Article Details

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
References
T. Kusano and M. Naito,"Comparison theorems for functional differential equations with deviating arguments," J. Math. Soc. Japan, 33(1981), 509-532
T. Kusano and M. Naito, "Boundedness of solutions of a class of higher order ordinary differential equations," J. Differential Equations, 46(1982), 32-45
B. Singh, "General functional differential equations and their asymptotic behavior," The Yokohama Math. J., 24(1976), 125-132.
B. Singh a.nd T. Kusa.no, "On asymptotic limits of nonoscillations in functional equations with retarded arguments," Hiroshima Math. J., 10(1980), 557-565
B. Singh a.nd T. Kusa.no, "Asymptotic behavior of oscillatory solutions of a. differential equation with deviating arguments," J. Math. Anal. Appl., 83(1981), 395-407
B. Singh, "Minima.I existence of nonoscillatory solutions in functional differential equations with deviating arguments," Rocky Mountain J. Math., 14(1984), 531-540