Document Type : Research Paper

Authors

• S. Ostadbashi
• J. Kazemzadeh

Department of Mathematics, Faculty of Sciences, Urmia University, Urmia, Iran.

Abstract

In this paper, we consider orthogonal stability of mixed type additive and cubic functional equation of the form $$f(2x+y)+f(2x-y)-f(4x)=2f (x+y)+2f(x-y)-8f(2x) +10f(x)-2f(-x),$$ with $x\bot y$, where $\bot$  is orthogonality in the sense of Ratz.

Keywords

• Hyers- Ulam- Aoki- Rassias stability
• mixed type additive and cubic functional equation
• orthogonality space