Simultaneous Approximation by a Polynomial and Its Derivatives
نویسنده
چکیده
Theorem. If fo is a continuous function on a compact set C without interior and with connected complement of the complex plane, and if fi, • • ■ i fn are continuous functions on a compact totally disconnected subset E of C, then there exists a sequence {pi} of polynomials such that pi-^fo uniformly on C as i—* , and pim—*fk uniformly on E as i—>», for lslk^n, where pi[k] is the kth derivative of pf.
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تاریخ انتشار 2010