In this paper, we mainly consider two problems. Firstly, we shall be concerned with the existence of two different solutions for the nonlinear following Schrodinger-Kirchhoff type system with sign-changing potential, where constants a> 0, b≥0. That is to say, when the potential V and the nonlinearity f are allowed to be sign-changing. By using the Ekeland’s variational principle and the Mountain Pass Theorem, we get the existence of two different solutions of the system.Secondly, we are interested in the following Kirchhoff type equation: where a, b> 0 are constants and μ is a positive parameter. Under some certain assump-tions on V, we prove that for q ∈(3,5), such a class of Kirchhoff type equation with critical growth has a positive ground solution via variational methods and a new version of global compactness lemma. |