Open AccessThe use of the isometry of function spaces with different numbers of variables in the theory of approximation of functions
Author(s) -
D. M. Bushev,
F. G. Аbdullayev,
I. V. Kal’chuk,
M. Imashkyzy
Publication year - 2021
Publication title -
karpatsʹkì matematičnì publìkacìï
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.63
H-Index - 4
eISSN - 2313-0210
pISSN - 2075-9827
DOI - 10.15330/cmp.13.3.805-817
Subject(s) - mathematics , isometric exercise , isometry (riemannian geometry) , exponential type , pure mathematics , function space , exponential function , function (biology) , entire function , construct (python library) , mathematical analysis , medicine , evolutionary biology , computer science , biology , programming language , physical therapy
In the work, we found integral representations for function spaces that are isometric to spaces of entire functions of exponential type, which are necessary for giving examples of equality of approximation characteristics in function spaces isometric to spaces of non-periodic functions. Sufficient conditions are obtained for the nonnegativity of the delta-like kernels used to construct isometric function spaces with various numbers of variables.