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

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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