APPROXIMATING CLASSES OF FUNCTIONS DEFINED BY A GENERALISED MODULUS OF SMOOTHNESS

ISSN: 2147-6268
Yayın Aralığı: Yılda 4 Sayı
Başlangıç: 2013
Yayıncı: -

In the present paper, we use a generalised shift operator in order to define a generalised modulus of smoothness. By its means, we definegeneralised Lipschitz classes of functions, and we give their constructive characteristics. Specifically, we prove certain direct and inverse types theorems inapproximation theory for best approximation by algebraic polynomials

Keywords:

generalised Lipschitz classes, generalised modulus of smoothness asymmetric generalised shift operator, theorem of coincidence of classes,

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Terez¨e 5, 10000 Prishtin¨e, Kosovo E-mail address: faton.berisha@uni-pr.edu N. Sh. Berisha, Faculty of Mathematics and Sciences, University of Prishtina, N¨ena
Terez¨e 5, 10000 Prishtin¨e, Kosovo E-mail address: nimete.berisha@gmail.com