题干

在平面直角坐标系中,质点在坐标平面内做直线运动,分别求下列位移向量的坐标.
(1)向量a→表示沿东北方向移动了2个单位长度;
(2)向量b→表示沿西偏北60°方向移动了4个单位长度;
(3)向量c→表示沿东偏南30°方向移动了6个单位长度.
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答案(点此获取答案解析)

解:建立方向坐标平面,如图所示;
(1)向量a→表示沿东北方向移动了2个单位长度;
a→

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