A. F. Andreev
Russia, 198504, Petergof, Universitetski pr.28
S.Peterburg State University
Faculty of Mathematics and Mechanics
I. A. Andreeva
Russia, 195251, Saint-Petersburg, Politekhnicheskaya str., 29,
Saint-Petersburg state technic university,
dept. of Higher mathematics
On a real (x,y)-plane a normal system of ordinary differential equations is considered, being the right parts are respectively quadratic and cubic forms of x and y with arbitrary constant coefficients. The task is to investigate the behavior of its trajectories on an extended (x,y)- plane or, in equivalent terms, in a Poincare circle. In Part I of this investigation all possible for this system topological types of a singular point O(0,0) are revealed, and criteria of their realization are formulated. Topological types of the point O are given: