.V. Kartashevskiy - Ph. D. (Eng.), Associate Professor, Department of Software and Management in Technical Systems, Volga State University of Telecommunications and Informatics (Samara) E-mail: ivk@psuti.ru I.A. Blatov - Dr. Sc. (Phys.-Math.), Professor, Head of Department of Higher Mathematics, Volga State University of Telecommunications and Informatics (Samara) E-mail: blatow@mail.ru Yu.A. Gerasimova - Post-graduate Student, Department of Higher Mathematics, Volga State University of Telecommunications and Informatics (Samara) E-mail: gerasimova.ju@yandex.ru