在某张航海图上,标明了三个观测点的坐标,如图,
、
、
,由三个观测点确定的圆形区域是海洋生物保护区.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/85fa0277-bee7-4f17-87e0-648d9fd00a9c.png?resizew=258)
(1)求圆形区域的面积;
(2)某时刻海面上出现渔船A,在观测点O测得A位于北偏东45°,同时在观测点B测得A位于北偏东
,求观测点B到A船的距离.(结果精确到到0.1,参考数据:
,
,
.);
(3)当渔船A由(2)中位置向正西方向航行时,是否会进入海洋生物保护区?通过计算回答.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19b62194097ac66a5093c57fca2f5b4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fbdef5d0c05acbf63fa72fa85c5bb45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/119670810b86ce07be0d45d0757715f3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/85fa0277-bee7-4f17-87e0-648d9fd00a9c.png?resizew=258)
(1)求圆形区域的面积;
(2)某时刻海面上出现渔船A,在观测点O测得A位于北偏东45°,同时在观测点B测得A位于北偏东
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/707d14deed56ff2667c9ddaeef35ebf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60fe7c20aaec12d3f7435131eb2abd69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8f55020399233fde5766da0f095a6a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f08cc928d14d8308aebb9e0395c4a0b.png)
(3)当渔船A由(2)中位置向正西方向航行时,是否会进入海洋生物保护区?通过计算回答.
更新时间:2021-06-11 10:10:18
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