已知
A(m,-n),B(-m,n),点C分[ ]
|
A .(m,n) |
B .(-3m,3n) |
|
C .(3m,-3n) |
D .(-m,n) |
若
G为△ABC的重心,则[ ]
|
A .1 |
B .-1 |
|
C .0 |
D .不确定 |
已知
A(m,-n),B(-m,n),点C分[ ]
|
A .(m,n) |
B .(-3m,3n) |
|
C .(3m,-3n) |
D .(-m,n) |
若
G为△ABC的重心,则[ ]
|
A .1 |
B .-1 |
|
C .0 |
D .不确定 |