1 . 如图,已知
为圆
的直径,
是圆
上的两个点,
是劣弧
的中点,
于
,
交
于
,交
于
.
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/3e0a26c204e24863a3a77dfbb24e801f.png)
(I)求证:![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/63f8fb1e75594a758078ca9be76bb8b5.png)
(II)求证:
.
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/967c22b19f344574b8c13e9fa4d91832.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/fd7b07f4c63f47c8b702d8e4940872ae.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/0afd82f357d146cea17399dd87277c1e.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/fd7b07f4c63f47c8b702d8e4940872ae.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/9629d0f6fe56454b87215fde0a912106.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/ec77c519c66a478d9b3cc38367963dc7.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/c369dd27e0a34d82bccc5ea1fed1000c.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/10370b89352a45e2a20663005d576b5f.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/ec77c519c66a478d9b3cc38367963dc7.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/a919d209e52a467dbb5632a5d6e4090a.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/07c9f7b3b5504a61bc194c0c210adb97.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/f43048372b7f485e9001b27c47f93b92.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/38685f44021a46eba7e46898c12567c5.png)
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/3e0a26c204e24863a3a77dfbb24e801f.png)
(I)求证:
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/63f8fb1e75594a758078ca9be76bb8b5.png)
(II)求证:
![](https://img.xkw.com/dksih/QBM/2016/9/14/1573022847942656/1573022854119424/STEM/6d75f4cd022b400499f008660dcd8693.png)
您最近一年使用:0次
2016-12-04更新
|
58次组卷
|
2卷引用:2017届山西长治二中等五校高三上学期联考一数学(理)试卷
2012·河北衡水·一模
2 . 如图,
是圆的两条平行弦,
,
交
于
、交圆于
,过
点的切线交
的延长线于
,
,
.
![](https://img.xkw.com/dksih/QBM/2013/1/21/1571105310400512/1571105316200448/STEM/07621d023a264552a14e51ad914afbed.png)
(1)求
的长;
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5c4cd264c97c1f261229925cc5a6761.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d1ee2efdb2c3b7c90198efc88010db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1299069da883e3285cea3f2d54ad1c36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b80ee363635d73f601654339028daec.png)
![](https://img.xkw.com/dksih/QBM/2013/1/21/1571105310400512/1571105316200448/STEM/07621d023a264552a14e51ad914afbed.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e2e1083b773e16d1e385072652f7319.png)
您最近一年使用:0次
11-12高三·山西·阶段练习
3 . 如图所示,在⊙O中,弦CD垂直于直径AB,求证:
.
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570748045828096/1570748051341312/STEM/73737106edb3450bacb22a52ea83f8ac.png?resizew=61)
![](https://img.xkw.com/dksih/QBM/2012/2/17/1570748045828096/1570748051341312/STEM/22d6661a9be74f4995815e54d48f6c88.png?resizew=184)
您最近一年使用:0次
4 . 几何证明选讲
如图,过点
分别作⊙
的切线
与割线
,
为切点,
与⊙
交于
两点,圆心
在
的内部,
,
与
交于点
.
(1)在线段
上是否存在一点
,使
四点共圆?若存在,请确定点
的位置;若不存在,请说明理由;
(2)若
,证明:
.
如图,过点
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/d3f7c8c2535346f49553bb4df6795004.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/84db6ec9974b4e4980f39ffd58ab6dc8.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/78f4e1778eef4a5eb5d5d8fb3782770a.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/f5213c81323944a2a81d341c9af35f07.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/506a56e586c1434dae85d76044bf8938.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/f5213c81323944a2a81d341c9af35f07.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/84db6ec9974b4e4980f39ffd58ab6dc8.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/6c0a8d323b47451495dccd736acbdfb0.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/84db6ec9974b4e4980f39ffd58ab6dc8.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/3442b847f17e46b8acdf08220d172ca7.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/eb5e6171718643b595203027615c7032.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/9f3328aacba94ae2af583c7ee34381de.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/d9a9137ac0a1487eb24a8a3fb71e3647.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/ac4979804a1849d0afcee14ff3eb152a.png)
(1)在线段
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/73a57ae9b48e4cfdbbbda51561ced2e8.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/6eed780c34a948648ef1a2b566673d42.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/c97b826ac57c4acb91163f84de8d6eae.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/6eed780c34a948648ef1a2b566673d42.png)
(2)若
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/81e251d8e06e409eae60820aad35f141.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/01fdd657f7ed4bfdb33190feab8b4583.png)
![](https://img.xkw.com/dksih/QBM/2016/11/25/1573179582693376/1573179589148672/STEM/8e6507a3881f4f838e76eb4189b9014a.png)
您最近一年使用:0次