名校
1 . 已知Rt△ABC中,CD是斜边AB上的高,BE是角平分线并且与CD交于F,CH⊥EF,垂足为H,延长CH与AB交于G.
![](https://img.xkw.com/dksih/QBM/2019/4/11/2180013395902464/2181526744260609/STEM/f6e41111c6ee45219076d0203b7050e1.png?resizew=265)
(1)求证:
;
(2)若AC=2BC,求证EA=5FD.
![](https://img.xkw.com/dksih/QBM/2019/4/11/2180013395902464/2181526744260609/STEM/f6e41111c6ee45219076d0203b7050e1.png?resizew=265)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1de0f9cba1248d3dd476fd1c6f0afe6d.png)
(2)若AC=2BC,求证EA=5FD.
您最近一年使用:0次
2 . 如图,AB为⊙O的直径,BD是⊙O的切线,连接AD交⊙O于E,若BD∥CE,AB交CE于M,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e4b0311cb57d78f465a57dc7f26353c.png)
![](https://img.xkw.com/dksih/QBM/2018/12/5/2090404214185984/2094345211813888/STEM/647c1bdc-8188-4995-bad2-424c20db0e6d.png)
您最近一年使用:0次
3 . [选修4-1:几何证明选讲]
如图,已知凸四边形
的顶点在一个圆周上,另一个圆的圆心
在
上,且与四边形
的其余三边相切.点
在边
上,且
.
求证:
,
,
,
四点共圆.
如图,已知凸四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e30e50e094cd2849e38859b36aad0b0c.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://img.xkw.com/dksih/QBM/2017/2/3/1619477902778368/1619477903532032/STEM/5cb641e06fd34edeba2a92b40698fc1b.png)
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13-14高三上·江苏南京·阶段练习
4 . 如图,
、
是圆
的半径,且
,
是半径
上一点:延长
交圆
于点
,过
作圆
的切线交
的延长线于点
.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ada5c15d7b42b2fb2836c3478ae5fb34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/167c86f47167a5bd8f5a7efeb3861ae5.png)
![](https://img.xkw.com/dksih/QBM/2014/1/2/1571451709734912/1571451715510272/STEM/5710690361ce43ed993e0bc517d42e80.png)
您最近一年使用:0次
5 . 如图,已知圆上是弧
=弧
,过点
的圆的切线
与
的延长线交于点
.
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/014cd8ff813446af83f6e21cde406a19.png)
(1)求证:
;
(2)求证:
.
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/7d65ebc7b7cb4d42ab78dccad8b65a2a.png)
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/516e8049bde640599240fd0abba02168.png)
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/aeec79396c7d4b3ebc730d7f7a64e422.png)
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/6e97d076626642bbb2df96af70aafa09.png)
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/5b8192d9ed8a4a97a348afbbdbe10cab.png)
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/4b5250e0e5444d18b7eaf14119250494.png)
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/014cd8ff813446af83f6e21cde406a19.png)
(1)求证:
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/1ec2d60f578a4231a91f135de7ea952b.png)
(2)求证:
![](https://img.xkw.com/dksih/QBM/2016/5/19/1572642802843648/1572642809176064/STEM/e3284c8c2a784740a413232713c30349.png)
您最近一年使用:0次