On One Approach to Investigation of Mechanical Systems

The paper presents some results of qualitative analysis of Kirchhoff's differential equations describing motion of a rigid body in ideal fluid in Sokolov's case. The research methods are based on Lyapunov's classical results. Methods of computer algebra implemented in the computer algebra system (CAS) “Mathematica” were also used. Combination of these methods allowed us to obtain rather detailed information on qualitative properties for some classes of solutions of the equations.