Results 21 to 30 of about 349 (66)
On the Orthogonal Stability of the Pexiderized Quadratic Equation
, 2005 The Hyers--Ulam stability of the conditional quadratic functional equation of Pexider type f(x+y)+f(x-y)=2g(x)+2h(y), x\perp y is established where \perp is a symmetric orthogonality in the sense of Ratz and f is odd.Comment: 10 pages, Latex; Changed ...
Aczél J. +12 more
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Superstability of functional equations related to spherical functions
Open Mathematics, 2017 In this paper we prove stability-type theorems for functional equations related to spherical functions. Our proofs are based on superstability-type methods and on the method of invariant means.
Székelyhidi László
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STABILITY, COHOMOLOGY VANISHING, AND NONAPPROXIMABLE GROUPS
Forum of Mathematics, Sigma, 2020 Several well-known open questions (such as: are all groups sofic/hyperlinear?) have a common form: can all groups be approximated by asymptotic homomorphisms into the symmetric groups $\text{Sym}(n)$ (in the sofic case) or the finite-dimensional unitary ...
MARCUS DE CHIFFRE +3 more
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Pseudo almost periodic solutions for a class of differential equation with delays depending on state
Advances in Nonlinear Analysis, 2019 In this paper, the exponential dichotomy, and Tikhonov and Banach fixed point theorems are used to study the existence and uniqueness of pseudo almost periodic solutions of a class of iterative functional differential equations of the ...
Zhao Hou Yu
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Hyers-Ulam stability of isometries on bounded domains-II
Demonstratio Mathematica, 2023 The question of whether there is a true isometry approximating the ε\varepsilon -isometry defined in the bounded subset of the nn-dimensional Euclidean space has long been considered an interesting question.
Choi Ginkyu, Jung Soon-Mo
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Approximate Homomorphisms of Ternary Semigroups
, 2005 A mapping $f:(G_1,[ ]_1)\to (G_2,[ ]_2)$ between ternary semigroups will be called a ternary homomorphism if $f([xyz]_1)=[f(x)f(y)f(z)]_2$. In this paper, we prove the generalized Hyers--Ulam--Rassias stability of mappings of commutative semigroups into ...
A. Cayley +22 more
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On a functional equation that has the quadratic-multiplicative property
Open Mathematics, 2020 In this article, we obtain the general solution and prove the Hyers-Ulam stability of the following quadratic-multiplicative functional equation:ϕ(st−uv)+ϕ(sv+tu)=[ϕ(s)+ϕ(u)][ϕ(t)+ϕ(v)]\phi (st-uv)+\phi (sv+tu)={[}\phi (s)+\phi (u)]{[}\phi (t)+\phi (v ...
Park Choonkil +4 more
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Satbility of Ternary Homomorphisms via Generalized Jensen Equation
, 2005 In this paper, we establish the generalized Hyers--Ulam--Rassias stability of homomorphisms between ternary algebras associted to the generalized Jensen functional equation $r f(\frac{sx+ty}{r}) = s f(x) + t f(y)$.Comment: 12 ...
Moslehian, Mohammad Sal +1 more
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Journal of Mathematics, Volume 2025, Issue 1, 2025.In this present work, we derive the solution of a quadratic functional equation and investigate the Ulam stability of this equation in Banach spaces using fixed point and direct techniques. Mainly, we examine the stability results in quasi‐β‐Banach spaces and quasi‐fuzzy β‐Banach spaces by means of direct method as well as quasi‐Banach spaces by means ...
Kandhasamy Tamilvanan +5 more
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On a type of exponential functional equation and its superstability in the sense of Ger [PDF]
, 2013 In this paper, we deal with a type exponential functional equation as follows $$f(xy)=f(x)^{g(y)},$$ where $f$ and $g$ are two real valued functions on a commutative semigroup.
Alimohammady, M. +2 more
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