aequationes mathematicae

, Volume 50, Issue 1–2, pp 143–190 | Cite as

Hyers-Ulam stability of functional equations in several variables

  • Gian Luigi Forti
Survey Papers

Summary

The paper is a survey about Hyers—Ulam stability of functional equations and systems in several variables.

Its content is divided in the following chapters:
  1. 1.—

    Introduction. Historical background.

     
  2. 2.—

    The additive Cauchy equation; Jensen's equation.

     
  3. 3.—

    The quadratic equation and the polynomial equation.

     
  4. 4.—

    The multiplicative Cauchy equation. Superstability.

     
  5. 5.—

    Approximately multiplicative linear maps in Banach algebras.

     
  6. 6.—

    Other equations and systems.

     
  7. 7.—

    Final remarks and open problems.

     

The bibliography contains 120 items.

AMS (1991) subject classification

39B22 39B32 39B52 

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Copyright information

© Birkhäuser Verlag 1995

Authors and Affiliations

  • Gian Luigi Forti
    • 1
  1. 1.Dipartimento di MatematicaUniversità degli Studi di MilanoMilanoItalia

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