Abstract
For metrics of sign-sensitive weight, a generalization of the Jackson theorem and an analog of the Dolzhenko theorem on the estimate of the variation of a function in terms of its least rational deviations are obtained. In the same metric, two-sided estimates for rational deviations of the function signx are given.
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Translated fromMatematickeskie Zametki, Vol. 60, No. 5, pp. 715–725, November, 1996.
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Ramazanov, A.R.K. Rational approximation with sign-sensitive weight. Math Notes 60, 536–543 (1996). https://doi.org/10.1007/BF02309168
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DOI: https://doi.org/10.1007/BF02309168