한국수학교육학회지시리즈B:순수및응용수학 (The Pure and Applied Mathematics)

  • 제27권1호
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  • Pages.25-33
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  • 2020
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  • 1226-0657(pISSN)
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  • 2287-6081(eISSN)
한국수학교육학회 (Korean Society of Mathematical Education)
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QUADRATIC (ρ1, ρ2)-FUNCTIONAL EQUATION IN FUZZY BANACH SPACES

  • Paokant, Siriluk (Department of Mathematics, Research Institute for Natural Sciences, Hanyang University) ;
  • Shin, Dong Yun (Department of Mathematics, University of Seoul)
  • 투고 : 2019.01.03
  • 심사 : 2019.07.19
  • 발행 : 2020.02.29
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초록

In this paper, we consider the following quadratic (ρ1, ρ2)-functional equation (0, 1) $$N(2f({\frac{x+y}{2}})+2f({\frac{x-y}{2}})-f(x)-f(y)-{\rho}_1(f(x+y)+f(x-y)-2f(x)-2f(y))-{\rho}_2(4f({\frac{x+y}{2}})+f(x-y)-f(x)-f(y)),t){\geq}{\frac{t}{t+{\varphi}(x,y)}}$$, where ρ2 are fixed nonzero real numbers with ρ2 ≠ 1 and 2ρ1 + 2ρ2≠ 1, in fuzzy normed spaces. Using the fixed point method, we prove the Hyers-Ulam stability of the quadratic (ρ1, ρ2)-functional equation (0.1) in fuzzy Banach spaces.

키워드

과제정보

Dong Yun Shin was supported by the University of Seoul in 2019.

참고문헌

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