共50条信息
已知向量\( \overset{→}{BA}=( \dfrac{1}{2}, \dfrac{ \sqrt{3}}{2}) \),\( \overset{→}{BC}=\left( \dfrac{ \sqrt{3}}{2}, \dfrac{1}{2}\right) \) 则\(\angle ABC=\)( )
进入组卷