On the Asymptotic Behaviors Associated with the Davison Functional Equation


Download PDF

Authors: M. A. TAREEGHEE, A. NAJATI AND J-H. BAE

DOI: 10.46793/KgJMat2605.777T

Abstract:

We prove the Hyers-Ulam stability of the Davison functional equation

f(x+ xy)+ f(y) = f (x + y)+ f(xy),

for a class of mappings from a normed algebra ???? (with a unit element 1) into a Banach space , on the restricted domain {(x,y) ∈ ???? × ???? :   min{∥x∥,∥y∥} ≥ d}, where d > 0 is a constant. As a result, we obtain some asymptotic behaviors of Davison mappings. In addition, we obtain the corollary that for every mapping g from a normed algebra ???? into a normed space , and for all positive real numbers r,s, one of the following two conditions must be valid:

 sup ∥g(x + y)+ g(xy)− g(x+ xy)− g(y)∥⋅∥x∥r ⋅∥y∥s = + ∞
x,y∈????

or

g(x+ y)+ g(xy) = g(x + xy)+ g(y).


Keywords:

Hyers-Ulam stability, Davison functional equation, asymptotic behavior.



References:

[1]   W. Benz, 191R1. Remark, Aequationes Math. 20 (1980), 307.

[2]   T. M. K. Davison, 191R1. Probem, Aequationes Math. 20 (1980), 306.

[3]   T. M. K. Davison, A Hosszú-like functional equation, Publ. Math. Debrecen 58 (2001), 505–513. https://doi.org/10.5486/PMD.2001.2326

[4]   R. Girgensohn and K. Lajkó, A functional equation of Davison and its generalization, Aequationes Math. 60(3) (2000), 219–224. https://doi.org/10.1007/s000100050148

[5]   K.-W. Jun, S.-M. Jung and Y.-H. Lee, A generalization of the Hyers-Ulam-Rassias stability of a functional equation of Davison, J. Korean Math. Soc. 41(3) (2004), 501–511. https://doi.org/10.4134/JKMS.2004.41.3.501

[6]   S.-M. Jung and P. K. Sahoo, Hyers-Ulam-Rassias stability of an equation of Davison, J. Math. Anal. Appl. 238(1) (1999), 297–304. https://doi.org/10.1006/jmaa.1999.6545

[7]   S.-M. Jung and P. K. Sahoo, On the Hyers-Ulam stability of a functional equation of Davison, Kyungpook Math. J. 40(1) (2000), 87–92.

[8]   S.-M. Jung and P. K. Sahoo, Hyers-Ulam-Rassias stability of a functional equation of Davison in rings, Nonlinear Funct. Anal. Appl. 11(5) (2006), 891–896.

[9]   A. Najati and P. K. Sahoo, On two pexiderized functional equations of Davison type, Kragujevac J. Math. 47(4) (2023), 539–544. https://doi.org/10.46793/KgJMat2304.539N