Orthogonal stability of the generalized quadratic functional equations in the sense of Rätz

• Autorzy: Aiemsomboon Laddawan , Sintunavarat Wutiphol

Identyfikatory

DOI

10.1515/dema-2019-0044

• Języki publikacji: EN

Abstrakty

EN

Let (X, ⊥) be an orthogonality module in the sense of Rätz over a unital Banach algebra A and Y be a real Banach module over A. In this paper, we apply the alternative fixed point theorem for proving the Hyers-Ulam stability of the orthogonally generalized k-quadratic functional equation of the form af(kx+y) + af(kx-y) = f(ax+ay) + f(ax-ay) + (2k2-2)f(ax) for some |k|>1, for all a∈A1:= {u∈A|‖u‖ = 1} and for all x,y∈X with x⊥y, where f maps from X to Y.

Słowa kluczowe

EN

fixed point method; orthogonally generalized quadratic functional equation; stability

PL

metoda punktu stałego; równanie funkcjonałów kwadratowych; stabilność

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2019
• Tom: Vol. 52, nr 1
• Strony: 523--530
• Opis fizyczny: Bibliogr. 16 poz.

Twórcy

autor

Aiemsomboon Laddawan

• Department of Mathematics and Statistics, Faculty of Science and Technology, Thammasat University Rangsit Center, Pathum Thani 12120, Thailand

autor

Sintunavarat Wutiphol

• Department of Mathematics and Statistics, Faculty of Science and Technology, Thammasat University Rangsit Center, Pathum Thani 12120, Thailand

Bibliografia

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Uwagi

PL

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).