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Hyers-Ulam stability of functional equations in several variables

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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.

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  1. Dipartimento di Matematica, Università degli Studi di Milano, Via C. Saldini 50, I-20133, Milano, Italia

    Gian Luigi Forti

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Forti, G.L. Hyers-Ulam stability of functional equations in several variables. Aeq. Math. 50, 143–190 (1995). https://doi.org/10.1007/BF01831117

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