题干

在平面直角坐标系中,i,j分别是与x轴、y轴正方向同向的单位向量,O为坐标原点,设向量=2i+j,=3i+kj,若A,O,B三点不共线,且△AOB有一个内角为直角,则实数k的所有可能取值的个数是                                                    ()

A:1

B:2

C:3

D:4

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答案(点此获取答案解析)

B

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