We obtain asymptotic equalities for the least upper bounds of the approximations of functions from theclasses \( {\widehat{L}}_{\beta, 1}^{\psi } \) by biharmonic Poisson operators in the integral metric.
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 69, No. 5, pp. 650–656, May, 2017.
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Zhyhallo, T.V., Kharkevych, Y.I. Approximating Properties of Biharmonic Poisson Operators in the Classes \( {\widehat{L}}_{\beta, 1}^{\psi } \) . Ukr Math J 69, 757–765 (2017). https://doi.org/10.1007/s11253-017-1393-8
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DOI: https://doi.org/10.1007/s11253-017-1393-8