Affiliation:
1. 1 Zhejiang Sci-Tech University Institute of Mathematics Hangzhou Zhejiang 310018 China
2. 2 China Institute of Metrology Hangzhou Zhejiang 310034 China
Abstract
In the present paper, we investigate monotone rational approximation. We prove that iff∊C[0, 1]is an increasing function on the interval [0, 1] thenRn*(f) ≦Clog2µ/n‖f‖, whereRn*(f) is the best approximation offby incrasing rational functions of order (n, n), µ > 1 matchesnin the equationn= log2µ/ω(f,µ−. With some new techniques created, this result essentially generalizes and improves previous result appeared in Zhou [10].
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