如图,在
中,以
为直径作
,
分别交
于点
,过点
作
的切线交
的延长线于点
,
.
(1)求证:
;
(2)若
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3355e2fa0ac6c675f02ee36c3ced4f2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6670479a0083dd2dfd5ad55b47b1ab6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82036e837edd9f726e614738a6514eba.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b30a8f02b0532e55378662ebf23847.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbe5f8a0ce57e2145ef4def733afe4d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1df12c042d2036edcf1bdfd9c0f41f35.png)
![](https://img.xkw.com/dksih/QBM/2020/2/7/2394073280135168/2394461839204352/STEM/0fd7931780f04198bf0e58cc41b49da4.png?resizew=163)
2019·山西·一模 查看更多[2]
更新时间:2020-02-08 10:07:59
|
【知识点】 圆与三角形的综合(圆的综合问题)
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】如图,
,
是
的高,
,
相交于点
,
是
的中点,
是
的外接圆.
(1)点B,C,D,E是否在以点M为圆心的同一个圆上?请说明理由.
(2)若
,
,求
外接圆的半径长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/6/b2ddc2a3-e46e-4cc8-8f8d-9225ec2658e1.png?resizew=318)
(1)点B,C,D,E是否在以点M为圆心的同一个圆上?请说明理由.
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54275b7e571660d0a9e0370fbfe5050b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56512504254ab7f574a717dd6830fb33.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】已知内接于
,
,射线
切
于点A,F为
上一点,连接
交
于点E,连接
.
(1)从①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4474c82ae786e175b5e603b81bc8018d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3636a141ab0dd2cc4c481c6d47cedfd.png)
(2)在(1)的条件下,已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8314bf44fd67afda08134a89cff2de72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e962f2eb895839b30c5651ccd4ec5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】阅读以下材料,并按要求完成相应的任务:
几何定论,是指变化的图形中某些几何元素的几何量保持不变(如定长、定角、定比、定积等),或几何元素间的某些性质或位置关系不变(如定点、定线、定方向等)如图①,点A为⊙O外一点,过点A作直线AC与⊙O相交于点B,C,点B'为点B关于OA的对称点,连接B'C交OA于点M,设⊙O的半径为R.
![](https://img.xkw.com/dksih/QBM/2022/5/9/2975841826152448/2977316809637888/STEM/e1badf2e-7aba-465d-bbf3-7eab10721e6a.png?resizew=641)
如图②,当过点A的直线与⊙O相切时,点B,C重合,可得R2=OA•OM.
如图③,当过点A的直线与⊙O相交时,证明R2=OA•OM.
证明:如图③,连接OC,CD.
∵B,B′关于OA对称,∴
,∴∠1=∠2(依据).
任务:
(1)上述证明过程中的依据是_____________;
(2)根据以上的证明提示,完成上述证明过程;
(3)如图③,若OA=5,OM=1,求⊙O的半径.
几何定论,是指变化的图形中某些几何元素的几何量保持不变(如定长、定角、定比、定积等),或几何元素间的某些性质或位置关系不变(如定点、定线、定方向等)如图①,点A为⊙O外一点,过点A作直线AC与⊙O相交于点B,C,点B'为点B关于OA的对称点,连接B'C交OA于点M,设⊙O的半径为R.
![](https://img.xkw.com/dksih/QBM/2022/5/9/2975841826152448/2977316809637888/STEM/e1badf2e-7aba-465d-bbf3-7eab10721e6a.png?resizew=641)
如图②,当过点A的直线与⊙O相切时,点B,C重合,可得R2=OA•OM.
如图③,当过点A的直线与⊙O相交时,证明R2=OA•OM.
证明:如图③,连接OC,CD.
∵B,B′关于OA对称,∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8b1c6721aa6462575d145aeb5a7b357.png)
任务:
(1)上述证明过程中的依据是_____________;
(2)根据以上的证明提示,完成上述证明过程;
(3)如图③,若OA=5,OM=1,求⊙O的半径.
您最近一年使用:0次