如图,在
中,边AB,AC的垂直平分线相交于点O,分别交BC与D、E.
(1)若∠BAC=120°,则∠DAE= .
(2)连接OA、OB、OC,
的周长为6cm,
的周长为14cm,求OA的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(1)若∠BAC=120°,则∠DAE= .
(2)连接OA、OB、OC,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a7ffcd1925a2b1259221c6a476152f7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/30/c3971f76-ff83-4a53-8c23-c283e3e4f071.png?resizew=375)
更新时间:2020-10-14 08:36:31
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解答题-证明题
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适中
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【推荐1】如图,
内接于
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交
于点
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作
交
的延长线于点
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(1)求证:
.
(2)若
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(3)在(2)的条件下, 连结
, 记
,探究
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(1)求证:
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(2)若
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名校
【推荐2】如图1,已知直线
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(2)如图2,
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解答题-证明题
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【推荐1】如图,在平行四边形
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解答题-问答题
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【推荐2】在图1,图2中,点E是矩形ABCD边AB上的一点,且AE=AD,请仅用无刻度的直尺按下列要求画图(保留画图痕迹,不写画法).
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