题目内容
A.(3,-4) B.(-3,4)
C.(3,4) D.(-3,-4)
D
A.(3,-4) B.(-3,4)
C.(3,4) D.(-3,-4)
若向量a=(3,2),b=(0,-1),则向量2b-a的坐标是
A.(3,-4)
B.(-3,4)
C.(3,4)
D.(-3,-4)