Document Type : Research Paper

Authors

1 Department of Mathematics,College of Education for pure science, University of Anbar, Ramadi,Iraq

2 Department of Mathematics,College of Education for pure science,University of Anbar, Ramadi,Iraq

Abstract

In this paper, investigate the approximation of unbounded functions in weighted space, by using trigonometric polynomials considered. We introduced type of polynomials piecewise monotone  having same local monotonicity as unbounded functions without affecting the order of huge error have a finite number of max. and min. unbounded functions that amount. In addition, we established not included any of extreme points of this functions,  of and closed subset γ on closed intervals  then there exist class of polynomials such that the best of approximation has high or order of and such that for  sufficiently great of the polynomials and functions have the same monotonicity at each of γ.

Keywords

Main Subjects

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