Inequalities of Jackson type for functions with values in Hilbert space

V.F. Babenko (Oles Honchar Dnipropetrovsk National University, Institute of Applied Mathematics and Mechanics of NAS of Ukraine), https://orcid.org/0000-0001-6677-1914
S.V. Savela (Дніпропетровський національний університет імені Олеся Гончара)

Abstract


We present the generalization of M.I. Chernykh's results about the estimate of the best $$$L_2$$$-approximation of periodic function $$$f$$$ by trigonometric polynomials by its $$$L_2$$$-modulus of continuity, in the case of functions with values in Hilbert space.

References


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DOI: https://doi.org/10.15421/240802

  

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Copyright (c) 2008 V.F. Babenko, S.V. Savela

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ISSN (Online): 2664-5009
ISSN (Print): 2664-4991
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