Applied Mathematics and Mechanics (English Edition) ›› 1994, Vol. 15 ›› Issue (5): 471-483.
蔺小林1, 党新益2
Lin Xiao-lin1, Dang xin-yi2
摘要: In this paper, (a) we rerise Theorem 2 of Ref [1] omit the condition V7>0.(b) we discuss the relative positions of six curves M(s2, r)=0, J(s2, r)=0, L(s2,r)=0, T(s2,r)=0,s2=s+2 and s2=s-2 Under the condition of the (1.3) distri-butions of limit cycles, we expand the variable regions of parameters (s, r) and clearly. show them in figure, (c) we study the (1, 3) distributions of limit cycles of one kind quadratic systems with two singular points at the infinite: and (d) we give a generalmethod to discuss the (1, 3) distibutions`of limit cycles of system (1.1) whatever there isone, two or three singular points at the infinite.