问题:
已知△ABC的三个内角A,B,C所对的边分别为a,b,c,
m
=(1,1-
3
sinB),
n
=(cosB,1)且
m
⊥
n
,
(1)求角B;
(2)若a+c=
3
b,判断△ABC的形状.
已知△ABC的三个内角A,B,C所对的边分别为a,b,c,
=(1,1-
sinB),
=(cosB,1)且
⊥
,
(1)求角B;
(2)若a+c=
b,判断△ABC的形状.
m |
3 |
n |
m |
n |
(1)求角B;
(2)若a+c=
3 |
参考答案: