问题
填空题
在边长为6的等边△ABC中,点M满足
|
答案
∵
=2BM
,MA
∴
=CM
+CB
=BM
+CB 2 3 BA
则
•CM
=(CB
+CB 2 3
)• BA
=|CB
|2+CB 2 3
•CB BA
=36-2 3
•BC
=36-BA
×6×6cos60°=242 3
故答案为:24
在边长为6的等边△ABC中,点M满足
|
∵
=2BM
,MA
∴
=CM
+CB
=BM
+CB 2 3 BA
则
•CM
=(CB
+CB 2 3
)• BA
=|CB
|2+CB 2 3
•CB BA
=36-2 3
•BC
=36-BA
×6×6cos60°=242 3
故答案为:24