Direct and inverse theorems for the Bézier variant of certain summation-integral type operators

Recently, the Bézier variant of some well known operators were introduced (cf. [8]-[9]) and their rates of convergence for bounded variation functions have been investigated (cf. [2], [10]). In this paper we establish direct and inverse theorems for the Bézier variant of the operators Mn introduced in [5] in terms of Ditzian-Totik modulus of smoothness wj\lambda(f,t) (0 \leqslant l \leqslant1 ). These operators include the well known Baskakov-Durrmeyer and Szász-Durrmeyer type operators as special cases.

Direct and inverse theorems for the Bézier variant of certain summation-integral type operators

Recently, the Bézier variant of some well known operators were introduced (cf. [8]-[9]) and their rates of convergence for bounded variation functions have been investigated (cf. [2], [10]). In this paper we establish direct and inverse theorems for the Bézier variant of the operators Mn introduced in [5] in terms of Ditzian-Totik modulus of smoothness wj\lambda(f,t) (0 \leqslant l \leqslant1 ). These operators include the well known Baskakov-Durrmeyer and Szász-Durrmeyer type operators as special cases.

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  • Remark 1 From (3.1)–(3.6), we get |Mn,α(f, x)− f(x)| CKϕλ f, α1/2ϕ1−λ(x) √ n In view of (1.3), this further gives |Mn,α(f, x)− f(x)| ωϕλ f, α1/2ϕ1−λ(x) √ n