Abstract
We establish two direct estimates by K-functionals of the rate of approximation by the Kantorovich operators in variable exponent Lebesgue spaces. They extend known results in the non-variable exponent Lebesgue spaces. The approach applied heavily relies on the boundedness of the Hardy–Littlewood maximal operator.
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This study is financed by the European Union-NextGenerationEU, through the National Recovery and Resilience Plan of the Republic of Bulgaria, Project No. BG-RRP-2.004-0008.
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B. R. Draganov and I. Gadjev have contributed equally to this work.
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This study is financed by the European Union-NextGenerationEU, through the National Recovery and Resilience Plan of the Republic of Bulgaria, Project No. BG-RRP-2.004-0008.
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Draganov, B.R., Gadjev, I. Direct Estimates of the Rate of Approximation by the Kantorovich Operator in Variable Exponent Lebesgue Spaces. Mediterr. J. Math. 21, 112 (2024). https://doi.org/10.1007/s00009-024-02650-z
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DOI: https://doi.org/10.1007/s00009-024-02650-z
Keywords
- Kantorovich operator
- Jackson-type estimate
- direct inequality
- direct estimate
- K-functional
- variable exponent Lebesgue space