On uniform polynomial approximation of functions that are analytic in finite number of non-intersecting continuums

S.B. Vakarchuk; M.B. Vakarchuk; V.I. Zabutna

doi:10.15421/240806

On uniform polynomial approximation of functions that are analytic in finite number of non-intersecting continuums

S.B. Vakarchuk (Academy of Customs Service of Ukraine), https://orcid.org/0000-0002-2562-8844
M.B. Vakarchuk (Oles Honchar Dnipropetrovsk National University), https://orcid.org/0000-0001-8606-9057
V.I. Zabutna (Oles Honchar Dnipropetrovsk National University)

Abstract

We show that some of results, obtained by S.N. Bernstein, on constructive function theory, under certain conditions, take place for uniform polynomial approximation of functions that are analytic in finite number of non-intersecting continuums. On the base of obtained results for certain class of analytic functions we calculate asymptotic values of some $$$n$$$-widths.

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References

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