TY - JOUR T1 - APPROXIMATING CLASSES OF FUNCTIONS DEFINED BY A GENERALISED MODULUS OF SMOOTHNESS AU - Berısha, Faton M. AU - Sh.berısha, Nimete PY - 2013 DA - December JF - Mathematical Sciences and Applications E-Notes JO - Math. Sci. Appl. E-Notes PB - Murat TOSUN WT - DergiPark SN - 2147-6268 SP - 84 EP - 89 VL - 1 IS - 2 LA - en AB - 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 KW - generalised Lipschitz classes KW - generalised modulus of smoothness KW - asymmetric generalised shift operator KW - theorem of coincidence of classes CR - F. M. Berisha. On coincidence of classes of functions defined by a generalized modulus of smoothness and the appropriate inverse theorem. Math. Montisnigri, 9:15–36, 1998. CR - N. Sh. Berisha and F. M. Berisha. Approximating classes of functions defined by operators of differentiation or operators of generalised translation by means of algebraic polynomials. Int. J. Math. Anal. (Ruse), 6(55):2709–2729, 2012. CR - M. K. Potapov and F. M. Berisha. Approximation of classes of functions defined by a gener- alized k-th modulus of smoothness. East J. Approx., 4(2):217–241, 1998. CR - M. K. Potapov and F. M. Berisha. Direct and inverse theorems of approximation theory for a generalized modulus of smoothness. Anal. Math., 25(3):187–203, 1999. CR - M. K. Potapov and F. M. Berisha. O svyazi mezhdu r-im obobshchennym medulem gladkosti i nailuchshimi priblizheniyami algebraicheskimi mnogochlenami. Fundam. Prikl. Mat., 5(2):563– 587, 1999. F. M. Berisha, Faculty of Mathematics and Sciences, University of Prishtina, N¨ena CR - 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 CR - Terez¨e 5, 10000 Prishtin¨e, Kosovo E-mail address: nimete.berisha@gmail.com UR - https://dergipark.org.tr/en/pub/mathenot/article/207648 L1 - https://dergipark.org.tr/en/download/article-file/182481 ER -