Some remarks on stability and solvability of linear functional equations.
Some remarks on the general theorem of the existence of iterative roots of homeomorphisms with a rational rotation number
We show that the theorem proved in [8] generalises the previous results concerning orientation-preserving iterative roots of homeomorphisms of the circle with a rational rotation number (see [2], [6], [10] and [7]).
Some remarks on the stability of the multi-Jensen equation
First a stability result of Prager-Schwaiger [Prager W., Schwaiger J., Stability of the multi-Jensen equation, Bull. Korean Math. Soc., 2008, 45(1), 133–142] is generalized by admitting more general domains of the involved function and by allowing the bound to be not constant. Next a result by Cieplinski [Cieplinski K., On multi-Jensen functions and Jensen difference, Bull. Korean Math. Soc., 2008, 45(4), 729–737] is discussed. Finally a characterization of the completeness of a normed space in...
Some reproducing identities for families of mean values.
Some theorems on differentiable solutions of a system of functional equations of n-th order
Some varieties of groupoids which consist of abelian group or group isotopes.
Special solutions of a functional equation
Special solutions of a functional equation
Stabilities of cubic mappings in fuzzy normed spaces.
Stability and superstability of ring homomorphisms on non-archimedean Banach algebras.
Stability aspects of arithmetic functions
Stability aspects of arithmetic functions, II
Stability of a 2-dimensional functional equation in a class of vector variable functions.
Stability of a bi-Jensen functional equation. II.
Stability of a Cauchy-Jensen functional equation in quasi-Banach spaces.
Stability of a functional equation coming from the characterization of the absolute value of additive functions.
Stability of a functional equation deriving from cubic and quartic functions.
Stability of a functional equation related to distance measure. II.
Stability of a generalization of the Fréchet functional equation
We prove some stability and hyperstability results for a generalization of the well known Fréchet functional equation, stemming from one of the characterizations of the inner product spaces. As the main tool we use a fixed point theorem for some function spaces. We end the paper with some new inequalities characterizing the inner product spaces.
Stability of a generalized Euler-Lagrange type additive mapping and homomorphisms in -algebras.