V.N. Orlov - Dr. Sc. (Phys.-Math.), Head of Department of Mathematics, Theory and Methods of Teaching Mathematics, Humanities and Education Science Academy «V.I. Vernadsky Crimean Federal University», Yalta E-mail: orlowvn@rambler.ru P.V. Khmara - Master, Department of Mathematics, Theory and Methods of Teaching Mathematics, Humanities and Education Science Academy «V.I. Vernadsky Crimean Federal University», Yalta E-mail: pavaluck@gmail.com T.B. Sejtvelieva - Master, Department of Mathematics, Theory and Methods of Teaching Mathematics, Humanities and Education Science Academy «V.I. Vernadsky Crimean Federal University», Yalta