Abstract
It is proved that if a function f(x) is convex on [a, b] and f ∈ LipK(f)α, 0<α<1, then the least uniform deviation of this function from rational functions of degree not higher than n does not exceed
(v is a natural number; C(α, v) depends only onα andv; K(f) is a Lipschitz constant; and
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Translated from Matematicheskie Zametki, Vol. 18, No. 6, pp. 845–854, December, 1975.
In conclusion, the author thanks E. P. Dolzhenko for stating the problem and guiding my work.
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Khatamov, A. The rational approximation of convex functions of the class Lip α. Mathematical Notes of the Academy of Sciences of the USSR 18, 1092–1096 (1975). https://doi.org/10.1007/BF01099987
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DOI: https://doi.org/10.1007/BF01099987