过抛物线y^2=2px(p>0)的焦点F的弦AB的倾斜角为a,那么弦长|AB|=
问题描述:
过抛物线y^2=2px(p>0)的焦点F的弦AB的倾斜角为a,那么弦长|AB|=
答案好象是2p/sin^2a
答
2p/sina
过抛物线y^2=2px(p>0)的焦点F的弦AB的倾斜角为a,那么弦长|AB|=
答案好象是2p/sin^2a
2p/sina