如图，在一笔直的海岸线l上有A、B两个观测站，AB=2km、从A测得船C在北偏东45°的方向，从B测得船C在北偏东22.5°的方向，则船C离海岸线l的距离（即CD的长）为_刷题宝

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如图，在一笔直的海岸线l上有A、B两个观测站，AB=2km、从A测得船C在北偏东45°的方向，从B测得船C在北偏东22.5°的方向，则船C离海岸线l的距离（即CD的长）为（　　）

A：4km

B：（2+ $\sqrt{2}$ ）km

C：2 $\sqrt{2}$ km

D：（4﹣ $\sqrt{2}$ ）km

上一题下一题 0.0难度选择题更新时间:2018-04-02 10:50:48

答案(点此获取答案解析）

B

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