O,A,B是平面三点.直线AB上有C,满足向量2AC+向量CB=0

问题描述:

O,A,B是平面三点.直线AB上有C,满足向量2AC+向量CB=0
求向量OC.
A.2OA-OB
B.-OA+2OB
C.2/3OA-1/3OB
D.-1/3OA+2/3OB

OC =OA+AC
OC=OB+BC
==> OC = 2(OA+AC)-(OB+BC)= 2OA-OB + 2AC+CB=2OA-OB 
选 A