Results 1 to 10 of about 1,646 (172)
A Variant of Jensen’s Functional Equation on Semigroups
Demonstratio Mathematica, 2016 We determine the solutions f : S → H of the following functional ...
Fadli Brahim +2 more
doaj +3 more sources
On the E-Hyperstability of the Inhomogeneous σ-Jensen’s Functional Equation on Semigroups
Abstract and Applied Analysis, 2023 In this paper, we study the hyperstability problem for the well-known σ-Jensen’s functional equation fxy+fxσy=2fx for all x,y∈S, where S is a semigroup and σ is an involution of S. We present sufficient conditions on E⊂ℝ+S2 so that the inhomogeneous form
M. Sirouni, S. Kabbaj
doaj +1 more source
AIMS Mathematics, 2023 For a neutral system with mixed discrete, neutral and distributed interval time-varying delays and nonlinear uncertainties, the problem of exponential stability is investigated in this paper based on the $ H_\infty $ performance condition.
Boonyachat Meesuptong +3 more
doaj +1 more source
New Generalizations of Jensen's Functional Equation [PDF]
Proceedings of the American Mathematical Society, 1995 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Haruki, Hiroshi +1 more
openaire +1 more source
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
openaire +1 more source
Fuzzy Stability of Jensen‐Type Quadratic Functional Equations [PDF]
Abstract and Applied Analysis, 2009 We prove the generalized Hyers‐Ulam stability of the following quadratic functional equations 2f((x + y)/2) + 2f((x − y)/2) = f(x) + f(y) and f(ax + ay) + (ax − ay) = 2a2f(x) + 2a2f(y) in fuzzy Banach spaces for a nonzero real number a with a ≠ ±1/2.
Jang, Sun-Young +3 more
openaire +3 more sources
On the stability of the squares of some functional equations
Annales Universitatis Paedagogicae Cracoviensis: Studia Mathematica, 2015 We consider the stability, the superstability and the inverse stability of the functional equations with squares of Cauchy’s, of Jensen’s and of isometry equations and the stability in Ulam-Hyers sense of the alternation of functional equations and of ...
Zenon Moszner
doaj +1 more source
Convex Duality in Constrained Portfolio Optimization [PDF]
, 1992 We study the stochastic control problem of maximizing expected utility from terminal wealth and/or consumption, when the portfolio is constrained to take values in a given closed, convex subset of R^d.
Cvitanić, Jakša, Karatzas, Ioannis
core +1 more source
On Jensen's functional equation
Aequationes Mathematicae, 1992 The following is offered as main result. Let \((G,\cdot)\) and \((H,+)\) be abelian groups, and \(e\) the neutral element of \((G,\cdot)\). The solutions \(f: G\to H\) of \(f(xy)+f(xy^{-1})=2f(x)\), \(f(e)=0\) are exactly the homomorphisms of \(G\to H\) if, and only if, either \(H\) has no element of order 2 or \([G:G^ 2]\leq 2\), where \(G^ 2:=\{x^ 2 ...
Vasudeva, H.L., Parnami, J.C.
openaire +2 more sources
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(
openaire +2 more sources