Infinitely Many Solutions For Two Classes Of Sublinear Elliptic Equations

In this thesis, we deal with the existence of infinitely many solutions for two classes of sublinear elliptic equations.In chapter one we introduc some basic knowledge of variational methods some theorems and lemmas which will be used in elliptic equationsIn chapter two and chapter three we deal with elliptic equations and where x∈RN,u:RNâ†'R and f:RN×Râ†'R.Under the assumptions that f(x,t) is odd for t, we let f(x,t) be sublinear or quasi-linear as|t|â†'0and|t|â†'+∞, we establish some existence criteria to guarantee that the above problem has infinitely many nontrival solutions by using the genus properties in critical point theory.