Positive Solutions For The Fractional Laplacian Equations With Critical Sobolev Exponents

In this paper,we will adapt the variational approach to study the existence of positive solutions for the following fractional laplacian problem(?) where ? is a real parameter,0<s<1,N>2s,?is a bounded domain in RN with smooth boundary(?)?.K(x)is a smooth function on ? and positive somewhere.We will prove an existence result of positive solutions of the above problem when A and K satisfy some assumptions.