题文
已知平行四边形OABC中(O为原点),
=(2,1),

=(1,2),则

·

=( )A.0B.2C.4D.5 题型:未知 难度:其他题型
答案
A解析
该题暂无解析
考点
据考高分专家说,试题“已知平行四边.....”主要考查你对 [向量数量积的运算 ]考点的理解。
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