# An elementary proof for the decomposition theorem of Wright convex functions

### Abstract

The main goal of this paper is to give a completely elementary proof for the decomposition theorem of Wright convex functions which was discovered by C. T. Ng in 1987. In the proof, we do not use transfinite tools, i.e., variants of Rodé’s theorem, or de Bruijn’s theorem related to functions with continuous differences.

### Keywords

Wright convexity; Jensen convexity; decomposition theorem

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*Annales Mathematicae Silesianae*,

*34*(1), 142-150. Retrieved from https://www.journals.us.edu.pl/index.php/AMSIL/article/view/13639

Institute of Mathematics, University of Debrecen, Hungary Hungary

https://orcid.org/0000-0003-2382-6035

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