A-stabilization and the ranges of complex polynomials on the unit disk

Abstract

Problems of stabilization of the unstable cycle of one-dimensional complex dynamical system are briefly discussed. These questions reduced to the problem of description of the ranges of polynomials $q(z) = q_1z + q_2z^2 +\dots + q_nz^n$ defined in the unit disk and normalized by the conditions $q(1) = 1 $ and this is the main subject of the present paper.