Acta mathematica scientia, Series B >
A SPECIAL MODULUS OF CONTINUITY AND THE K-FUNCTIONAL
Received date: 2013-09-30
Revised date: 2015-10-22
Online published: 2016-10-25
We consider the questions connected with the approximation of a real continuous 1-periodic functions and give a new proof of the equivalence of the special Boman-Shapiro modulus of continuity with Peetre's K-functional. We also prove Jackson's inequality for the approximation by trigonometric polynomials.
Key words： modulus of continuity; K-functional; Jackson's theorem
Nadezhda DOLMATOVA . A SPECIAL MODULUS OF CONTINUITY AND THE K-FUNCTIONAL[J]. Acta mathematica scientia, Series B, 2016 , 36(5) : 1531 -1540 . DOI: 10.1016/S0252-9602(16)30088-1
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