Voronovskaja's Theorem and Iterations for Complex Bernstein Polynomials in Compact Disks

In this paper, firstly we prove the Voronovskaja's convergence theorem for complex Bernstein polynomials in compact disks in C, centered at origin, with quantitative estimates of this convergence. Secondly, we study the approximation properties of the iterates of complex Bernstein polynomials and we prove that they preserve in the unit disk (beginning with an index) the univalence, starlikeness, convexity and spirallikeness.