在△ABO中,OA =(2cosα,2sinα) , OB =(5cosβ,5sinβ) ,若 OA • OB =-5 ,则S △ABC = BA 5 2 3 EA 5 2 3 .
在△ABO中,OA =(2cosα,2sinα) , OB =(5cosβ,5sinβ) ,若 OA • OB =-5 ,则S △ABC = BA 5 2 3 EA 5 2 3 .
发布时间:2025-05-19 23:08:32
在△ABO中,OA =(2cosα,2sinα) , OB =(5cosβ,5sinβ) ,若 OA • OB =-5 ,则S △ABC = BA 5 2 3 EA 5 2 3 .