The Asymptotic Accuracy of Rational Best Approximations to e’ on a Disk
نویسنده
چکیده
The method described by D. Braess (J. Approx. Theory 40 (1984), 375-379) is applied to study approximation of ez on a disk rather than an interval. Let E,, be the distance in the supremum norm on Izl 0 be integers, and let R,, be the set of rational functions of type (m, n). Let E,, denote the error in best Chebyshev approximation of type (m, n) to ez on the disk ]z] 0, i.e., where ]] @I] = supii, cp ] $(z)]. We will show THEOREM 1.
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تاریخ انتشار 2003