Results 11 to 20 of about 6,655 (246)
Stability of a Bi-Jensen Functional Equation II
Journal of Inequalities and Applications, 2009 We investigate the stability of the bi-Jensen functional equation II f((x+y)/2,z)−f(x,z)−f(y,z)=0, 2f(x,(y+z)/2)−f(x,y)−f(x,z)=0 in the spirit of Găvruta.
Lee Yang-Hi, Jun Kil-Woung, Jung Il-Sook
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On a Jensen Type Functional Equation [PDF]
Journal of Applied Analysis, 2007 Suppose that \(M\) is a Abelian group in which the unique division by 2 and 3 is performable and \(S\) is an abstract cone satisfying the cancellation law. In this paper the author proves that if \(f:M\to S\) is a solution of the Jensen functional equation, then it is a solution of the following equation \[ 3(b-1) f\biggl(\frac{x+y+z}{3}\biggr)+ f(x)+f(
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Jensen’s and the quadratic functional equations with an endomorphism [PDF]
Proyecciones (Antofagasta), 2017 We determine the solutions f : S → H of the generalized Jensen’s functional equation f (x + y) + f (x + φ(y)) = 2f (x), x,y ∈ S,and the solutions f : S → H of the generalized quadratic functional equation f (x + y) + f (x + φ(y)) = 2f (x) + 2f (y), x,y ∈ S,where S is a commutative semigroup, H is an abelian group (2-torsion free in the first ...
Sabour, KH, Kabbaj, S
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Some hyperstability and stability results for the Cauchy and Jensen equations
Journal of Inequalities and Applications, 2022 In this paper we give some hyperstability and stability results for the Cauchy and Jensen functional equations on restricted domains. We provide a simple and short proof for Brzdȩk’s result concerning a hyperstability result for the Cauchy equation.
Mohammad Bagher Moghimi, Abbas Najati
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A Fixed Point Approach to the Stability of a Cauchy-Jensen Functional Equation
Abstract and Applied Analysis, 2012 We find out the general solution of a generalized Cauchy-Jensen functional equation and prove its stability. In fact, we investigate the existence of a Cauchy-Jensen mapping related to the generalized Cauchy-Jensen functional equation and prove its ...
Jae-Hyeong Bae, Won-Gil Park
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A Fixed Point Approach to the Stability of Quadratic Functional Equation with Involution
Fixed Point Theory and Applications, 2008 Cădariu and Radu applied the fixed point method to the investigation of Cauchy and Jensen functional equations. In this paper, we will adopt the idea of Cădariu and Radu to prove the Hyers-Ulam-Rassias stability of the quadratic functional equation
Zoon-Hee Lee, Soon-Mo Jung
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A Variant of Jensen’s Functional Equation on Semigroups
Demonstratio Mathematica, 2016 Abstract We determine the solutions f : S → H of the following functional equation f(xy) + f(σ(y)x) = 2f(x); x; y ∈ S; and the solutions f1; f2; f3 : M → H of the functional equation f1(xy) + f2(σ(y)x) = 2f31(x); x; y ∈ M; where S is a semigroup, M is a monoid, H is an abelian ...
B. Fadli, Driss Zeglami, Samir Kabbaj
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On Jensen’s and the quadratic functional equations with involutions [PDF]
Proyecciones (Antofagasta), 2017 We determine the Solutions f : S → H of the generalized Jensen’s functional equation f( x + σ(y)) + f( x + τ(y)) = 2f(x), x , y∈ Sand the solutions f : S → H of the generalized quadratic functional equationf ( x + σ(y)) + f (x + τ(y)) = 2f (x) + 2f (y), x, y ∈ S,where S is a commutative semigroup, H is an abelian group (2-torsion free in the first ...
Fadli, B. +3 more
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Functional Differential Equations and Jensen’s Inequality [PDF]
Journal of Mathematical Analysis and Applications, 1987 The authors study various types of stability of the functional differential equations \(x'(t)=F(t,x_ t)\) where \(x_ t(s)=x(t+s),\)- h\(\leq s\leq 0\), and h is a positive constant. The main tool is the Lyapunov functionals. These functionals satisfy certain conditions involving functions which verify Jensen's inequality.
Becker, Leigh C +2 more
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Fuzzy Stability of Quadratic Functional Equations
Advances in Difference Equations, 2010 The fuzzy stability problems for the Cauchy additive functional equation and the Jensen additive functional equation in fuzzy Banach spaces have been investigated by Moslehian et al.
Dong Yun Shin +3 more
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