Results 21 to 30 of about 767 (107)
Continuous horizontally rigid functions of two variables are affine [PDF]
, 2011 Cain, Clark and Rose defined a function $f\colon \RR^n \to \RR$ to be \emph{vertically rigid} if $\graph(cf)$ is isometric to $\graph (f)$ for every $c \neq 0$.
Balka, Richárd, Elekes, Márton
core +2 more sources
Recursive procedure in the stability of Fréchet polynomials
, 2014 By means of a new stability result, established for symmetric and multi-additive mappings, and using the concepts of stability couple and of stability chain, we prove, by a recursive procedure, the generalized stability of two of Fréchet’s polynomial ...
D. Dăianu
semanticscholar +1 more source
A Levi–Civita Equation on Monoids, Two Ways
Annales Mathematicae Silesianae, 2022 We consider the Levi–Civita equation f(xy)=g1(x)h1(y)+g2(x)h2(y)f\left( {xy} \right) = {g_1}\left( x \right){h_1}\left( y \right) + {g_2}\left( x \right){h_2}\left( y \right) for unknown functions f, g1, g2, h1, h2 : S → ℂ, where S is a monoid.
Ebanks Bruce
doaj +1 more source
On the generalized Hyers-Ulam-Rassias stability problem of radical functional equations
Journal of Inequalities and Applications, 2012 In this paper, the generalized Hyers-Ulam-Rassias stability problem of radical quadratic and radical quartic functional equations in quasi-β-Banach spaces and then the stability by using subadditive and subquadratic functions for radical functional ...
S. Kim, Y. Cho, M. Eshaghi Gordji
semanticscholar +1 more source
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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Hyers-Ulam stability of exact second-order linear differential equations [PDF]
, 2012 In this article, we prove the Hyers-Ulam stability of exact second-order linear differential equations. As a consequence, we show the Hyers-Ulam stability of the following equations: second-order linear differential equation with constant coefficients ...
Badrkhan Alizadeh +3 more
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Hyers-Ulam stability of functional equations in matrix normed spaces
, 2013 In this paper, we prove the Hyers-Ulam stability of the Cauchy additive functional equation and the quadratic functional equation in matrix normed spaces.MSC:47L25, 39B82, 46L07, 39B52.
Jung Rye Lee, D. Shin, Choonkill Park
semanticscholar +1 more source
, 2012 In this paper, we give the general solution of the functional equation $$\big\{\|f(x)+f(y)\|,\|f(x)-f(y)\|\big\}=\big\{\|x+y\|,\|x-y\|\big\}\qquad(x,y\in X)$$ where $f:X\to Y$ and $X,Y$ are inner product spaces. Related equations are also considered. Our
Maksa, Gyula, Páles, Zsolt
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The Cosine-Sine Functional Equation on Semigroups
Annales Mathematicae Silesianae, 2022 The primary object of study is the “cosine-sine” functional equation f(xy) = f(x)g(y)+g(x)f(y)+h(x)h(y) for unknown functions f, g, h : S → ℂ, where S is a semigroup.
Ebanks Bruce
doaj +1 more source
Jensen's functional equation on the symmetric group $\bold{S_n}$
, 2011 Two natural extensions of Jensen's functional equation on the real line are the equations $f(xy)+f(xy^{-1}) = 2f(x)$ and $f(xy)+f(y^{-1}x) = 2f(x)$, where $f$ is a map from a multiplicative group $G$ into an abelian additive group $H$.
C.T. Ng +6 more
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