在
中,内角A,B,C的对边分别为a,b,c,点O是
的外心,
.
(1)求角A;
(2)若
外接圆的周长为
,求
周长的取值范围,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ac6babcae1fef212f9376b6ad226fba.png)
(1)求角A;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa2eb9837d18069575f16397d175a6a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
更新时间:2022-05-21 21:53:09
|
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适中
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【推荐1】已知在
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(1)若
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(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f82a30d6b232dc4d8f35d2d6e0e0f42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
(2)求
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【推荐2】已知
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0d84187b9afd7fe20909ede0b82b858.png)
(1)求角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)求
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适中
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9b52345323a7eb6bf44e8447e10e9ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd35cc30ce0d3a5ca2bbeec79a9ce1ee.png)
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