Premium
Simultaneous Approximation by Polynomial Projection Operators
Author(s) -
Xie T. F.,
Zhou S. P.
Publication year - 1996
Publication title -
mathematische nachrichten
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.913
H-Index - 50
eISSN - 1522-2616
pISSN - 0025-584X
DOI - 10.1002/mana.3211810113
Subject(s) - mathematics , pointwise , projection (relational algebra) , bounded function , interpolation (computer graphics) , polynomial , sequence (biology) , degree (music) , function (biology) , mathematical analysis , pure mathematics , algorithm , image (mathematics) , physics , artificial intelligence , evolutionary biology , biology , computer science , acoustics , genetics
Abstract Pointwise estimates are obtained for simultaneous approximation of a function f and its derivatives by means of an arbitrary sequence of bounded projection operators with some extra condition (1.3) (we do not require the operators to be linear) which map C [‐1,1] into polynomials of degree n , augmented by the interpolation of f at some points near ±1. The present result essentially improved those in [BaKi3], and several applications are discussed in Section 4.