Abstract
In the paper, we consider the problem of uniform approximation of a continuous function defined on a compact metric space \(X\) by elements of the sum of two algebras in the space of all continuous functions on \(X\). We prove a Chebyshev-type theorem for characterization of best approximation.
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The authors wish to express gratitude to the referee for valuable remarks.
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Asgarova, A.K., Ismailov, V.É. A Chebyshev-Type Theorem Characterizing Best Approximation of a Continuous Function by Elements of the Sum of Two Algebras. Math Notes 109, 15–20 (2021). https://doi.org/10.1134/S0001434621010028
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DOI: https://doi.org/10.1134/S0001434621010028