The limit periodic solutions of multifrequency systems described by the volterra-type integro-differential equations

摘要

The analytical systems of n order with n pure imaginer roots of a characteristic equation are investigated. The equations of the systems depend on a small limit periodic perturbation in a form of a function exponentially approaching to a periodic function as independent variable grows. If all frequencies of the system are commensurable, the existence conditions of the limit periodic solutions (for the system of order 4) are given by basing on the terms of third degree of the equations.