Abstract
We obtain estimates for the approximation of functions of the class W r H ω, where ω(t) is a convex modulus of continuity such that tω′(t) does not decrease, by algebraic polynomials with regard for the position of a point on the segment [−1, 1]. The estimates obtained cannot be improved for all moduli of continuity simultaneously.
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Motornyi, V.P. On Exact Estimates for the Pointwise Approximation of the Classes WrHω by Algebraic Polynomials. Ukrainian Mathematical Journal 53, 916–937 (2001). https://doi.org/10.1023/A:1013399801684
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DOI: https://doi.org/10.1023/A:1013399801684