Estimates of approximation of elements of Hilbert space by subspaces spanned by given unit expansion

V.F. Babenko; S.V. Savela

doi:10.15421/241006

Estimates of approximation of elements of Hilbert space by subspaces spanned by given unit expansion

V.F. Babenko (Oles Honchar Dnipropetrovsk National University), https://orcid.org/0000-0001-6677-1914
S.V. Savela (Oles Honchar Dnipropetrovsk National University)

Abstract

The exact inequalities of the Jackson-Chernih type of the approximation in the Hilbert space are obtained.

Keywords

best approximation; exact inequalities; Hilbert space; expansion unit; group unitary operators

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References

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