Bi-center problem for some classes of Z2-equivariant systems
نویسندگان
چکیده
We investigate the simultaneous existence of two centers (bi-center) for two families of planar Z2-equivariant differential systems. First we present necessary and sufficient conditions for the existence of an isochronous bi-center for a planar Z2-equivariant cubic system having two centers at the points (−1, 0) and (1, 0), completing the study done by Liu and Li (2011). Next, we give conditions for the existence of a bi-center and study its isochronicity for a planar Z2-equivariant quintic system having two weak foci or centers at the points (−1, 0) and (1, 0). We also give an example of a cubic system with three isochronous centers.
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عنوان ژورنال:
- J. Computational Applied Mathematics
دوره 320 شماره
صفحات -
تاریخ انتشار 2017