在文 [1 ],[2 ],[3]中已给出了圆锥曲线的一些性质 ,本文再做进一步讨论 ,得到一系列更深入的结果 .1　引理以下讨论都是在极坐标系中 ,圆锥曲线E :ρ = ep1 -ecosθ,θ ∈ [0 ,2π) ;E上点A( ρ1 ,θ1 ) ,B( ρ2 ,θ2 ) ,C( ρ3,θ3) ,D( ρ4,θ4) ;则对应极点F(即焦点 )的准 Some properties of conic curves have been given in [1], [2], and [3]. This paper discusses further and obtains a series of more in-depth results. 1 Lemma The following discussion is in the polar coordinate system. Conic curve E: ρ = ep1 -ecosθ, θ ∈ [0, 2π) ; E points A (ρ1, θ1), B (ρ2, θ2), C (ρ3, θ3), D (ρ4, θ4); Corresponding to the pole F (ie focus)