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Acta Applicandae Mathematica

, Volume 62, Issue 1, pp 23–130 | Cite as

On the Stability of Functional Equations and a Problem of Ulam

  • Themistocles M. Rassias
Article

Abstract

In this paper, we study the stability of functional equations that has its origins with S. M. Ulam, who posed the fundamental problem 60 years ago and with D. H. Hyers, who gave the first significant partial solution in 1941. In particular, during the last two decades, the notion of stability of functional equations has evolved into an area of continuing research from both pure and applied viewpoints. Both classical results and current research are presented in a unified and self-contained fashion. In addition, related problems are investigated. Some of the applications deal with nonlinear equations in Banach spaces and complementarity theory.

stability functional equations Cauchy difference semigroup inequalities approximate 

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© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Themistocles M. Rassias
    • 1
  1. 1.Department of MathematicsNational Technical University of Athens, Zografou CampusAthensGreece

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