On a question of J.M. Rassias

Authors

  • W. Fechner University of Silesia Katowice, Poland

Keywords:

Functional inequality, subadditive mappings, Dini derivatives

Abstract

Answering a problem posed by John Michael Rassias we study the following functional inequality: $$f(x + y + xy) \leq f(x) + f(y) + f(xy) $$ with real unknown mapping \(f\). DOI: 10.1017/S0004972713000889

Published

2014-03-25

Issue

Vol. 89 No. 3 (2014)

Section

Articles
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