SOME DIRECT AND INVERSE THEOREMS OF APPROXIMATION OF FUNCTIONS IN JACOBI-DUNKL DISCRETE HARMONIC ANALYSIS

In this paper, several direct and inverse theorems in terms of the best approximations functions moduli smoothness are proved concerning approximation from space $$\mathbb {L}_{2}^{(\alpha ,\beta )}$$ by partial sums Jacobi-Dunkl series. For purpose, we use generalized translation operator which was defined Vinogradov.