The Ulam stability of various equations (eg, differential, difference, integral, and functional)
concerns the following issue: how much does an approximate solution of an equation differ …

Using the direct method, we prove the Ulam stability results for the general linear functional
equation of the form∑ i= 1 m A i (f φ i (x¯))= D (x¯) for all x¯∈ X n, where f is the unknown …

Quite often (eg, using numerical methods), we are only able to find approximate solutions of
some equations, and it is necessary to know the size of the difference between such …

This article aims to use various fixed-point techniques to study the stability issue of the
impulsive Volterra integral equation in the sense of Ulam–Hyers (sometimes known as …

A FIXED POINT THEOREM IN ULTRAMETRIC n-BANACH SPACES AND HYPERSTABILITY
RESULTS Page 1 Fixed Point Theory, 24(2023), No. 2, 433-458 DOI: 10.24193/fpt-ro.2023.2.01 …

Gähler (Untersuchungen über verallgemeinerte m-metrische Räume. I”. German. Math
Nachr 40, 165–189, 1969) investigated m-metric spaces and in particular m-normed spaces …

In this paper, we deduce some hyperstability results for a generalized class of
homogeneous Pexiderized functional equations, expressed as∑ ρ∈ Γ fx ρ. y= ℓ f (x)+ ℓ g …

In this article, with simple and short proofs without applying fixed point theorems, some
hyperstability results corresponding to the functional equations of Cauchy and Jensen are …

We propose the definition of quasi-n-normed spaces and prove some new results on fixed
points theory related to weak contractions in this framework. We prove the existence and …

In this article, we utilize a special version of some recent fixed point theorem to investigate
the hyperstability of the following generalized quadratic functional equation with F is the …