Three - Dimensional Functional Equations And The Stability Of Quadratic - Cubic Functional Equations

In this paper, we investigate the stability of cubic functional equation in Felbin’s type fuzzy space and the stability of quadratic-cubic functional equation in Felbin’s type fuzzy space and non-Archimedean space.In first chapter, we give the stability of a cubic functional equation in Felbin’s type fuzzy Banach space; In chapter 2, we use fixed point and direct method to prove the HUR stability of quadratic-cubic equation in Felbin’s type fuzzy Banach space; In chapter 3, we prove the stability of quadratic-cubic equation in non-Archimedean space.