论文部分内容阅读
贵刊2006年第8期刊登了惠润科老师的一篇《圆锥曲线的一个性质及应用》,文中提出圆锥曲线的一个性质:过圆锥曲线的焦点F作倾斜角为α的直线l与圆锥曲线交于A、B两点(点A在B的上方),且F分AB的比为λ,e为离心率,则cos2α=(λ-1)2e2(λ+1)2.惠润科老师并利用方程、结合韦达定理、
Published in the eighth issue of 2006 Huh Yunke a “conic curve of a nature and application of” the paper proposed a property of the conic: over the center of the conic F as a tilt angle α of the straight line l and cone Curve to point A, B (point A in the B above), and F points AB ratio of λ, e is the eccentricity, then cos2α = (λ-1) 2e2 (λ +1) Teacher and use of equations, combined with Vedic theorem,