A Functional equation related to inner product spaces in non-archimedean normed spaces [PDF]
Advances in Difference Equations, 2011 In this paper, we prove the Hyers-Ulam stability of a functional equation related to inner product spaces in non-Archimedean normed spaces. 2010 Mathematics Subject Classification: Primary 46S10; 39B52; 47S10; 26E30; 12J25.
shin Dong +4 more
doaj +3 more sources
Fuzzy Stability of Generalized Mixed Type Cubic, Quadratic, and Additive Functional Equation [PDF]
Journal of Inequalities and Applications, 2011 In this paper, we prove the generalized Hyers-Ulam stability of generalized mixed type cubic, quadratic, and additive functional equation, in fuzzy Banach spaces. 2010 Mathematics Subject Classification: 39B82; 39B52.
Shin Dong +4 more
doaj +3 more sources
Nonlinear approximation of an ACQ-functional equation in nan-spaces [PDF]
Fixed Point Theory and Applications, 2011 In this paper, using the fixed point and direct methods, we prove the generalized Hyers-Ulam stability of an additive-cubic-quartic functional equation in NAN-spaces. Mathematics Subject Classification (2010) 39B52·47H10·26E30·46S10·
Lee Jung +2 more
doaj +2 more sources
Orthogonal Stability of an Additive-Quadratic Functional Equation [PDF]
Fixed Point Theory and Applications, 2011 Using the fixed point method and using the direct method, we prove the Hyers-Ulam stability of an orthogonally additive-quadratic functional equation in orthogonality spaces. (2010) Mathematics Subject Classification: Primary 39B55; 47H10; 39B52; 46H25.
Park Choonkil
doaj +2 more sources
On the stability of pexider functional equation in non-archimedean spaces
Journal of Inequalities and Applications, 2011 In this paper, the Hyers-Ulam stability of the Pexider functional equation in a non-Archimedean space is investigated, where σ is an involution in the domain of the given mapping f.
Vaezpour Seiyed +2 more
doaj +1 more source
Superstability of generalized cauchy functional equations
Advances in Difference Equations, 2011 In this paper, we consider the stability of generalized Cauchy functional equations such as Especially interesting is that such equations have the Hyers-Ulam stability or superstability whether g is identically one or not.
Chung Soon-Yeong, Lee Young-Su
doaj +2 more sources
Approximate *-derivations and approximate quadratic *-derivations on
Journal of Inequalities and Applications, 2011 In this paper, we prove the stability of *-derivations and of quadratic *-derivations on Banach *-algebras. We moreover prove the superstability of *-derivations and of quadratic *-derivations on C*-algebras.
Park Choonkil, Jang Sun
doaj +1 more source
Fuzzy stability of a mixed type functional equation [PDF]
Journal of Inequalities and Applications, 2011 In this paper, we investigate a fuzzy version of stability for the functional equation f ( x + y + z ) - f ( x + y ) - f ( y + z ) - f ( x + z ) + f ( x ) + f ( y ) + f ( z ) = 0 in the sense of Mirmostafaee and Moslehian.
Jin Sun, Lee Yang-Hi
doaj +2 more sources
On the Ulam-Hyers stability of a quadratic functional equation [PDF]
Journal of Inequalities and Applications, 2011 The Ulam-Hyers stability problems of the following quadratic equation r 2 f x + y r + r 2 f x - y r = 2 f ( x ) + 2 f ( y ) , where r is a nonzero rational number, shall be treated.
Park Won-Gil +2 more
doaj +2 more sources
The Ulam Stability Problem for the Functional Equation f(x * g(y)) = f(x) f(y) [PDF]
, 2020 We present a solution of Ulam’s stability problem for the functional equation f(x * g(y)) = f(x)f(y) with vector-valued map f. Mathematics Subject Classification.
Badora, Roman
core +1 more source