Pointwise estimates for polynomial approximation on the semiaxis
نویسندگان
چکیده
منابع مشابه
Pointwise estimates for polynomial approximation on the semiaxis
We state some pointwise estimates for the rate of weighted approximation of a continuous function on the semiaxis by polynomials. Similarly to a previous result in C[−1, 1] due to Z. Ditzian and D. Jiang [2], we consider weighted φ moduli of continuity, where 0 ≤ λ ≤ 1. The results we obtain bridge the gap between an old pointwise estimate by V.M. Fedorov [4] and the recent norm estimates.
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ژورنال
عنوان ژورنال: Journal of Approximation Theory
سال: 2010
ISSN: 0021-9045
DOI: 10.1016/j.jat.2010.06.002