ERROR QUANTIFICATION FOR APPROXIMATION IN GENERALIZED ZYGMUND CLASSES USING THREE-HARMONIC POISSON INTEGRALS

Year 2026, Volume: 16 Issue: 2, 188 - 203, 03.02.2026

Xhevat Krasniqi

Abstract

This paper examines the error in approximation within generalized Zygmund classes using three-harmonic Poisson integrals. The error is measured using two moduli of continuity of order two, within the relevant norm, providing a clear understanding of how the approximation works.

Keywords

Degree of approximation , Three-harmonic Poisson integrals , Generalized Zygmund class , Three-harmonic Poisson kernel , Modulus of continuity of order two

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