
20.(本小题满分12分)如图,在平面四边形ABCD中,∠ABC=∠ACD=π/3,AB=6.
(1)若△ABC的面积为9√3/2,求AC
(2)在(1)的条件下,若AD=√26,求Cos2D.
作者:网络 来源: 2022-06-09 10:49:41 阅读:次
20.(本小题满分12分)如图,在平面四边形ABCD中,∠ABC=∠ACD=π/3,AB=6. (1)若△ABC的面积为9√3/2,求AC (2)在(1)的条件下,若AD=√26,求Cos2D.
20.(本小题满分12分)如图,在平面四边形ABCD中,∠ABC=∠ACD=π/3,AB=6.
(1)若△ABC的面积为9√3/2,求AC
(2)在(1)的条件下,若AD=√26,求Cos2D.