QUADRATIC (ρ<sub>1</sub>, ρ<sub>2</sub>)-FUNCTIONAL EQUATION IN FUZZY BANACH SPACES
Quadratic(ρ1, p2)-functional Equation in Fuzzy Banach Spaces
한국수학교육학회지시리즈B:순수및응용수학 / Journal of the Korean Society of Mathematical Education Series B: The Pure and Applied Mathematics, (P)1226-0657; (E)2287-6081
2020, v.27 no.1, pp.25-33
https://doi.org/https://doi.org/10.7468/jksmeb.2020.27.1.25
Paokant, Siriluk
(Department of Mathematics, Research Institute for Natural Sciences, Hanyang University)
Shin, Dong Yun
(Department of Mathematics, University of Seoul)
Paokant, Siriluk,
&
Shin, Dong Yun.
(2020). QUADRATIC (ρ<sub>1</sub>, ρ<sub>2</sub>)-FUNCTIONAL EQUATION IN FUZZY BANACH SPACES. 한국수학교육학회지시리즈B:순수및응용수학, 27(1), 25-33, https://doi.org/https://doi.org/10.7468/jksmeb.2020.27.1.25
Abstract
In this paper, we consider the following quadratic (ρ<sub>1</sub>, ρ<sub>2</sub>)-functional equation (0, 1) <TEX>$$N(2f({\frac{x+y}{2}})+2f({\frac{x-y}{2}})-f(x)-f(y)-{\rho}_1(f(x+y)+f(x-y)-2f(x)-2f(y))-{\rho}_2(4f({\frac{x+y}{2}})+f(x-y)-f(x)-f(y)),t){\geq}{\frac{t}{t+{\varphi}(x,y)}}$$</TEX>, where ρ<sub>2</sub> are fixed nonzero real numbers with ρ<sub>2</sub> ≠ 1 and 2ρ<sub>1</sub> + 2ρ<sub>2</sub>≠ 1, in fuzzy normed spaces. Using the fixed point method, we prove the Hyers-Ulam stability of the quadratic (ρ<sub>1</sub>, ρ<sub>2</sub>)-functional equation (0.1) in fuzzy Banach spaces.
- keywords
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fuzzy Banach space,
quadratic (<tex> ${\rho}_1$</tex>,
<tex> ${\rho}_2$</tex>)-functional equation,
fixed point method,
Hyers-Ulam stability