The problem of tracing on output variable with reference to linear and nonlinear multivariate dynamic systems is considered at the incomplete information on a state vector and in the supposition about not smoothness of demanded signals. By the standard approaches in problem solving of control and the observations are representation of the initial system in appropriate canonical forms and subsequent synthesis of these problems, which generally do not coincide. Thus, for problem solving of control and the observations will be utilized different conversions of the initial model of a control plant, that entails necessity of application of the laborious procedure of mutual inverse count of coordinates.