The powers of the bivariate Bernstein operators.
We prove some results which give explicit methods for determining an upper bound for the rate of approximation by means of operators preserving a cone. Thenwe obtain some quantitative results on the rate of convergence for some sequences of linear shape-preserving operators.
In this note we give the Voronovskaya theorem for some linear positive operators of the Szasz-Mirakjan type defined in the space of functions continuous on [0,+∞) and having the exponential growth at infinity. Some approximation properties of these operators are given in [3], [4].
AMS classification: 41A36, 41A10, 41A25, 41Al7.