1 . 如图,在四棱锥
中,
平面
,底面
是菱形,
,
,
,
分别是棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/3/2c3ae9c9-ad07-48d8-b6a2-648bae048570.png?resizew=208)
(1)证明:
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb8fb552b9e21dbaba74d11aa747790.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6184f3b929dda3c1b3b35b9aec448118.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47891397990336f55f96bd66d367758b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/3/2c3ae9c9-ad07-48d8-b6a2-648bae048570.png?resizew=208)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/053af8641980763a7f0e77beefe0712d.png)
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名校
2 . 已知函数
.
(1)讨论函数
的单调性;
(2)当
时,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ea1a650ffa47f1f85c45a13acf50c9c.png)
(1)讨论函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f76ee2d48fe9913fbd8d957b572dc48a.png)
您最近一年使用:0次
2019-08-02更新
|
1397次组卷
|
2卷引用:云南省昆明市2018-2019学年高二下学期期末考试数学(理)试题
真题
3 . 选修4—1:几何证明选讲 如图,直线AB为圆的切线,切点为B,点C在圆上,∠ABC的角平分线BE交圆于点E,DB垂直BE交圆于D.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/1/5365865e-1cc9-47a2-9e47-f3464ca9a3c5.png?resizew=160)
(Ⅰ)证明:DB=DC;
(Ⅱ)设圆的半径为1,BC=
,延长CE交AB于点F,求△BCF外接圆的半径.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/1/5365865e-1cc9-47a2-9e47-f3464ca9a3c5.png?resizew=160)
(Ⅰ)证明:DB=DC;
(Ⅱ)设圆的半径为1,BC=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
您最近一年使用:0次
2019-01-30更新
|
3916次组卷
|
12卷引用:2013年全国普通高等学校招生统一考试理科数学(新课标1卷)
2013年全国普通高等学校招生统一考试理科数学(新课标1卷)2013年全国普通高等学校招生统一考试文科数学(新课标1卷)(已下线)2014年高考数学文二轮专题复习与测试选修4-1几何证明选讲练习卷(已下线)2014届甘肃省兰州一中高考模拟一理科数学试卷(已下线)2014届甘肃省兰州一中高考模拟一文科数学试卷2015届黑龙江省哈尔滨六中高三上学期期末考试理科数学试卷2015届江西省吉安市第一中学高三上学期第二次阶段考试文科数学试卷2015届陕西省西安长安区一中高三上学期第三次质检理科数学卷2015届陕西省西安长安区一中高三上学期第三次质检文科数学卷2016届甘肃省会宁县一中高三上第四次月考理科数学试卷2016届湖北省宜昌市一中高三上学期12月月考数学试卷河北省武邑中学2017届高三下学期第一次质检考试数学(文)试题
4 . (本小题满分10分,几何证明选讲)
如图,P是⊙O外一点,PA是切线,A为切点,割线PBC与⊙O相交于点B,C,PC=2PA,D为PC的中点,AD的延长线交⊙O于点E.证明:AD·DE=2PB2.
如图,P是⊙O外一点,PA是切线,A为切点,割线PBC与⊙O相交于点B,C,PC=2PA,D为PC的中点,AD的延长线交⊙O于点E.证明:AD·DE=2PB2.
![](https://img.xkw.com/dksih/QBM/2015/4/30/1572088588263424/1572088594489344/STEM/a212503859e743bc83edcb31e4f9a019.png)
您最近一年使用:0次
2016-12-03更新
|
220次组卷
|
2卷引用:2015届江苏省扬州中学高三3月期初考试数学试卷
5 . 如图直线
经过圆
上的点
,OA=OB,CA=CB,圆
交直线
于点
、
,其中
在线段
上,连接
、
.
(1)证明:直线
是圆
的切线;
(2)若
,圆
的半径为
,求线段
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.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/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(1)证明:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae15f5d07adc869220ad68d0462a8301.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://img.xkw.com/dksih/QBM/2016/10/9/1573058872705024/1573058879307776/STEM/5b7d7e65592f4907a97015c96d17f62f.png)
您最近一年使用:0次
6 . 选修4-1:几何证明选讲
如图,
是
的外接圆,
的平分线
交
于
,交
于
,连接
并延长, 交
于
,交
于
.
![](https://img.xkw.com/dksih/QBM/2016/9/7/1573003126251520/1573003132870656/STEM/a5e23fa7201644d1bf658198a0a2c24e.png)
(1)证明:
;
(2)若
求
的长.
如图,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/880be04496b4e06b1c47d433d880b442.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd936a2405709574af0a73543d94ad9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6062582a0a1679aa777451f25008411d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/880be04496b4e06b1c47d433d880b442.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdc93e193fad261689949a52819753f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://img.xkw.com/dksih/QBM/2016/9/7/1573003126251520/1573003132870656/STEM/a5e23fa7201644d1bf658198a0a2c24e.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5c2123f90f931140fe9f85a3e61e30d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04a30bf456a72760e9a91e070752d8a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
2016-12-04更新
|
120次组卷
|
3卷引用:2016届山西晋城市高三下学期三模考试理数学试卷
12-13高三·河南南阳·阶段练习
7 . 如图,在
中,
是
的角平分线,
的外接圆交
于点
,
.
![](https://img.xkw.com/dksih/QBM/2016/6/7/1572696996036608/1572697002213376/STEM/a1d2f57cf6d74c838b101b1424485b37.png)
(1)证明:
;
(2)当
,
时,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd936a2405709574af0a73543d94ad9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0427054c47e348f35771872fd0215a8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c71855e55064d1dc59eabe43e73a881.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/846071242f981289741ad19f4e7190cf.png)
![](https://img.xkw.com/dksih/QBM/2016/6/7/1572696996036608/1572697002213376/STEM/a1d2f57cf6d74c838b101b1424485b37.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679372e54c59c5cf67931b12b9833e02.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca036d049f5205cf04cb1b9c5cd03f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72f7d9f5e71bfef8188b1216c1276c2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
2016-12-02更新
|
728次组卷
|
7卷引用:2014届河南省方城一高高三第一次调研(月考)考试理科数学试卷