如图,在Rt
ABC中,∠BCA=90°.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/4/f478c277-019b-4c03-a548-cc492dd82369.png?resizew=225)
(1)用尺规作AB的垂直平分线MN交AC于点D;(不写作法,保留作图痕迹)
(2)连接 BD若AD=4,CD=2,求∠DBC的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/4/f478c277-019b-4c03-a548-cc492dd82369.png?resizew=225)
(1)用尺规作AB的垂直平分线MN交AC于点D;(不写作法,保留作图痕迹)
(2)连接 BD若AD=4,CD=2,求∠DBC的正弦值.
2021·广东阳江·二模 查看更多[6]
2021年广东省阳江市阳东区七校九年级下学期模拟联考数学试题(已下线)专题28.14 锐角三角函数(全章复习与巩固)(知识讲解)-2022-2023学年九年级数学下册基础知识专项讲练(人教版)(已下线)专题1.16 《直角三角形的边角关系》全章复习与巩固(知识讲解)-2022-2023学年九年级数学下册基础知识专项讲练(北师大版)(已下线)专题1.16 《解直角三角形》全章复习与巩固(知识讲解)-2022-2023学年九年级数学下册基础知识专项讲练(浙教版)(已下线)专题7.14 锐角三角函数(全章复习与巩固)(知识讲解)-2022-2023学年九年级数学下册基础知识专项讲练(苏科版)福建省泉州市台商投资区2022-2023学年九年级上学期期末考试数学试题
更新时间:2022-03-09 17:03:52
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