Approximate Drygas mappings on a set of measure zero

  • Muaadh Almahalebi Ibn Tofail University.
Palabras clave: Drygas functional equation, stability, Baire category theorem, First category, Lebesgue measure, ecuación funcional de Drygas, estabilidad, teorema de categorías de Baire, primera categoría, medida de Lebesgue.


Let R be the set of real numbers, Y be a Banach space and f : R →Y. We prove the Hyers-Ulam stability for the Drygas functional equationf (x + y) + f (x - y) = 2f (x) + f (y) + f (-y) for all (x, y) ∈ Ω, where Ω⊂ R2 is of Lebesgue measure 0.

Biografía del autor/a

Muaadh Almahalebi, Ibn Tofail University.
Department of Mathematics, Faculty of Sciences.


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Cómo citar
Almahalebi, M. (2017). Approximate Drygas mappings on a set of measure zero. Proyecciones. Revista De Matemática, 35(2), 225-233.