Limit cycles for 3-monomial differential equations

作者:Gasull, Armengol; Li, Chengzhi; Torregrosa, Joan*
来源:Journal of Mathematical Analysis and Applications, 2015, 428(2): 735-749.
DOI:10.1016/j.jmaa.2015.03.039

摘要

lAre study planar polynomial differential equations that in complex coordinates write as (z) over dot = Az + Bz(z)(k)(-l) + Cz(m) (z) over tilde (n). We prove that for each p is an element of N there are differential equations of this type having at least p limit cycles. Moreover, for the particular case (z) over dot = Az + B (z) over bar + Cz(m)(z) over bar (n), which has homogeneous nonlinearities, we show examples with several limit cycles and give a condition that ensures uniqueness and hyperbolicity of the limit cycle.