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Approximation with Positive Linear Operators and Linear Combinations pp 67–87Cite as

Pointwise Estimates for Linear Combinations

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Part of the book series: Developments in Mathematics ((DEVM,volume 50))

Abstract

It was pointed out by Feilong and Zongben [56] that the Baskokov operators with the weight function φ 2(x) = x(1 + x) are non-concave on [0, ∞). By using the Ditzian–Totik modulus \(\omega _{\varphi ^{\lambda }}^{r}(f,t)\) of r-th order with \(r \in \mathbb{N},0 \leq \lambda <1\) they established the following four main results for the classical Baskakov operators.

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Authors and Affiliations

  1. Department of Mathematics, Netaji Subhas Institute of Technology, New Delhi, India

    Vijay Gupta

  2. Department of Mathematics, University of Architecture Civil Engineering and Geodesy, Sofia, Bulgaria

    Gancho Tachev

Authors
  1. Vijay Gupta
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  2. Gancho Tachev
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Gupta, V., Tachev, G. (2017). Pointwise Estimates for Linear Combinations. In: Approximation with Positive Linear Operators and Linear Combinations. Developments in Mathematics, vol 50. Springer, Cham. https://doi.org/10.1007/978-3-319-58795-0_5

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