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Sharp upper and lower estimates for the approximation of bivariate functions by sums of univariate functions

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Abstract

We obtain two-sided sharp inequalities for the uniform approximation of bivariate functions by sums of univariate functions on step polygons of the xy plane.

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Authors and Affiliations

  1. Department of Earth Science and Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK

    Muhammad Ismayilov

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  1. Muhammad Ismayilov
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Correspondence to Muhammad Ismayilov.

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The author declares that he has no Conflict of interest. I declare that I have no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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Communicated by S. Ponnusamy.

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Ismayilov, M. Sharp upper and lower estimates for the approximation of bivariate functions by sums of univariate functions. J Anal (2024). https://doi.org/10.1007/s41478-024-00787-4

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  • DOI: https://doi.org/10.1007/s41478-024-00787-4

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