The objective of this work is to design control strategies which optimize composition of production, technology stock and their rates in a nonlinear model of economic growth. The optimal control problem of technology investment is formulated for a discounted utility function which correlates the amount of sales and production diversity. The maximum principle of Pontryagin is applied for designing optimal nonlinear dynamics. Quasioptimal feedbacks of the rational type for balancing the dynamical system are constructed. Properties of techno-economic trajectories are examined for different tangent slopes generated by technology intensities. These properties correspond to the trends of economic growth intrinsic to econometric data.