APPROXIMATION OF PERIODIC FUNCTIONS BY SUB-MATRIX MEANS OF THEIR FOURIER SERIES

Year 2020, Volume: 10 Issue: 1, 279 - 287, 01.01.2020

X. Z. Krasniqi

Abstract

Some results on approximation of periodic functions are extended in two directions: Improving the degree of approximation of periodic functions by sub-matrix means of its Fourier series and such degree is applicable for a wider class of summbility matrices in the sense of their entries in which class of sequences belongs to.

Keywords

Fourier series, degree of approximation, periodic functions, non-decreasing sequences, Cesaro submethod.

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