“…Let us note that various optimal control problems in linear fractional-order systems with the Caputo derivatives are studied, e.g., in [1, 14-16, 21, 25] (see also the references therein for possible applications), where suitable variants of the maximum principle, methods of variational calculus and convex analysis, and methods related to the problem of moments are applied to find a solution. Moreover, in [9], a reduction scheme close to that proposed in the paper is developed on the basis of an approximation of fractional-order differential equations with the Caputo derivatives by first-order functional differential equations of a retarded type. However, the present paper follows a different approach that relies on the representation formula for solutions to linear fractional-order differential equations with the Caputo derivatives [8], does not require any approximation as an auxiliary intermediate step, and is more straightforward.…”