Results 11 to 20 of about 1,022 (204)

Hyperstability of Some Functional Equations on Restricted Domain [PDF]

Journal of Function Spaces, 2017
The paper concerns functions which approximately satisfy, not necessarily on the whole linear space, a generalization of linear functional equation. A Hyers-Ulam stability result is proved and next applied to give conditions implying the hyperstability ...
Anna Bahyrycz, Jolanta Olko
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Asymptotic Hyperstability of a Class of Linear Systems under Impulsive Controls Subject to an Integral Popovian Constraint [PDF]

Abstract and Applied Analysis, 2013
This paper is focused on the study of the important property of the asymptotic hyperstability of a class of continuous-time dynamic systems. The presence of a parallel connection of a strictly stable subsystem to an asymptotically hyperstable one in the ...
M. De la Sen, A. Ibeas, S. Alonso-Quesada   +2 more
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On Hyperstability of the Cauchy Functional Equation in n-Banach Spaces

Mathematics, 2020
We present some hyperstability results for the well-known additive Cauchy functional equation f(x+y)=f(x)+f(y) in n-normed spaces, which correspond to several analogous outcomes proved for some other spaces. The main tool is a recent fixed-point theorem.
Janusz Brzdęk, El-sayed El-hady
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Hyperstability of the k-Cubic Functional Equation in Non-Archimedean Banach Spaces

Journal of Mathematics, 2020
Using the fixed point approach, we investigate a general hyperstability results for the following k-cubic functional equations fkx+y+fkx−y=kfx+y+kfx−y+2kk2−1fx, where k is a fixed positive integer ≥2, in ultrametric Banach spaces.
Youssef Aribou, Mohamed Rossafi
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Stability and hyperstability of a quadratic functional equation and a characterization of inner product spaces

Demonstratio Mathematica, 2018
We have proved theHyers-Ulam stability and the hyperstability of the quadratic functional equation f (x + y + z) + f (x + y − z) + f (x − y + z) + f (−x + y + z) = 4[f (x) + f (y) + f (z)] in the class of functions from an abelian group G into a Banach ...
Kim Gwang Hui, El-Fassi Iz-iddine, Park Choonkil   +2 more
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Hyperstability for a Generalized Class of Pexiderized Functional Equations on Monoids via Páles’ Approach

Mathematics
In this paper, we deduce some hyperstability results for a generalized class of homogeneous Pexiderized functional equations, expressed as ∑ρ∈Γfxρ.y=ℓf(x)+ℓg(y), x,y∈M, which is inspired by the concept of Ulam stability.
Rashad M. Asharabi, Muaadh Almahalebi
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About robust hyperstability and dissipativity of linear time-invariant dynamic systems subject to hyperstable controllers and unstructured delayed state and output disturbances

Cogent Engineering, 2018
This paper considers the robust asymptotic closed-loop hyperstability of a nominal time-invariant plant with an associate strongly positive real transfer function subject to unstructured disturbances in the sate and output.
M. De la Sen
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Stability and Hyperstability of Ternary Hom-Multiplier on Ternary Banach Algebra

Axioms
In this article, we investigate the 3D additive-type functional equation. Next, we introduce the ternary hom-multiplier in ternary Banach algebras using the concepts of ternary homomorphisms and ternary multipliers.
Vahid Keshavarz, Mohammad Taghi Heydari, Douglas R. Anderson   +2 more
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The hyperstability of AQ-Jensen functional equation on 2-divisible abelian group and inner product spaces

Annals of the West University of Timisoara: Mathematics and Computer Science, 2015
In this paper, we prove the hyperstability of the following mixed additive-quadratic-Jensen functional equation 2f(x+y2)+f(x−y2)+f(y−x2)=f(x)+f(y)$$2f({{x + y} \over 2}) + f({{x - y} \over 2}) + f({{y - x} \over 2}) = f(x) + f(y)$$ in the class of ...
EL-Fassi Iz-iddine, Kabbaj Samir
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Hyperstability of the Fréchet Equation and a Characterization of Inner Product Spaces [PDF]

Journal of Function Spaces and Applications, 2013
We prove some stability and hyperstability results for the well-known Fréchet equation stemming from one of the characterizations of the inner product spaces. As the main tool, we use a fixed point theorem for the function spaces.
Anna Bahyrycz, Janusz Brzdęk, Magdalena Piszczek, Justyna Sikorska   +3 more
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