1 . 已知
点在圆
直径
的延长线上,
切圆
于点
,
是
的平分线交
于点
,交于
点
.
(1)求
的度数;
(2)
,求
.
![](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/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9abaeba15f3abdd877bc701af52c5cd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.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/8fabb884dc5f9609de491245463bbe9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7316430d26a6f4bcc0bdadfd1a5330a.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed647eac1acfd975e27b759678919f4f.png)
您最近一年使用:0次
2 .
中,
,
,
于点
,
于点
.
(1)如图1,作
的角平分线
交
于点
,连接
.求证:
;
(2)如图2,连接
,点
与点
关于直线
对称,连接
、
.
![](https://img.xkw.com/dksih/QBM/2017/1/12/1619453242490880/1619453243326464/STEM/a301af284afc4d32afe3253c7caee63f.png)
①依据题意补全图形;
②用等式表示线段
、
、
之间的数量关系,并加以证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c42ed2e5bd5a0f033e24008697bf4963.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a320a6a242be91347d1b241f6313251.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d320f180419175d75eebc618cc458b39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
(1)如图1,作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/868ff1350bd72625328c85c3097cd85e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/061b0a17b2590efbeb08c9778a5e1fa4.png)
(2)如图2,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e55e398e8520d8a36fb5a625a085b8.png)
![](https://img.xkw.com/dksih/QBM/2017/1/12/1619453242490880/1619453243326464/STEM/a301af284afc4d32afe3253c7caee63f.png)
①依据题意补全图形;
②用等式表示线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
您最近一年使用:0次
3 . 如图,点A在直径为15的⊙O 上,PBC是过点O的割线,且PA=10,PB=5.
(1)求证:PA与⊙O相切;
(2)求
的值.
(1)求证:PA与⊙O相切;
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa642ee56d9ded0bca025b84aa76df18.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/19/1f92f78e-d272-4acf-ab80-792ed3a413a0.png?resizew=189)
您最近一年使用:0次
4 . 选修4-1:几何证明选讲
如图,在
中,作平行于
的直线交
于
,交
于
,如果
和
相交于点
,
和
相交于点
,
的延长线和
相交于
.
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/025f290d513d47179edd624ee16d8ae8.png)
证明:(1)
;
(2)
.
如图,在
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/ba8397e50422458b9a9b6d6227c580af.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/e6575f855cc54fef9b837a4597d56b70.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/1d956a080b6340c3b32f2531c4633696.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/7d11d9bbcb3446f98a548d417e204a1c.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/a306713665284ef6b00220a57d0fa2e7.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/368334a480b4446da818c2ab024cfaa6.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/807e8d50e1924f7ab5361e26c24c75e2.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/61cd59f187a242e791abd77d49f5f1dd.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/556c3a1ee58641aba1955bb805a27e74.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/92bfa0685fe746c390a74a1457a4c2fc.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/b4dc5ecb3b5b4d9485816f39a5886051.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/0837b939b2f5475e83bac419d3a493ab.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/92bfa0685fe746c390a74a1457a4c2fc.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/e6575f855cc54fef9b837a4597d56b70.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/40c9e40a819d4f2aa1fd9748dbcc2c59.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/025f290d513d47179edd624ee16d8ae8.png)
证明:(1)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/7ba6472e7bc04212b670fa5ab17f7188.png)
(2)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1573148011216896/1573148017401856/STEM/716b6c3c3ba948bd80951ebe5be6a9e9.png)
您最近一年使用:0次
5 . 选修4-1:几何证明选讲:
如图,在
中,作平行于
的直线交
于
,交
于
,如果
和
相交于点
,
和
相交于点
,
的延长线和
相交于
.
![](https://img.xkw.com/dksih/QBM/2016/11/9/1573137495523328/1573137502019584/STEM/7e480414d7644e99b3bedade61253ae1.png)
证明:(Ⅰ)
;
(Ⅱ)
如图,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f2333da32638ec636fa1e69e750ca4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.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/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2c3d2cba96f6f03520c0b3f6e4da03e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2c3d2cba96f6f03520c0b3f6e4da03e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://img.xkw.com/dksih/QBM/2016/11/9/1573137495523328/1573137502019584/STEM/7e480414d7644e99b3bedade61253ae1.png)
证明:(Ⅰ)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6f13465b7525536ef4422beda3441c8.png)
(Ⅱ)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4777cee255b0bb459909a1e618bacbb.png)
您最近一年使用:0次
6 . 选修4-1:几何证明选讲
如图, 在
中,
, 以
为直径的
交
于点
是边
上一点,
与
交于点
,连接
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/7/64182108-52c3-4f6c-a006-62598306bf46.png?resizew=134)
(1)证明:
四点共圆;
(2)若
,求
的值.
如图, 在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3c65edad25ddd666cdce0d7e5afefc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8e9ec412ea0355e4e5cd06c60e5fee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/7/64182108-52c3-4f6c-a006-62598306bf46.png?resizew=134)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50d6e29d79a1bd34722833d4c059644f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cb1355df4d66c6e4baebae0cc4c5908.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d51e8dd98c23601d6bf4aab286be5f8.png)
您最近一年使用:0次
2016-12-05更新
|
123次组卷
|
3卷引用:2017届云南昆明市高三上学期摸底统测数学(理)试卷
7 . 选修4-1:几何证明选讲
如图,圆
是
的外接圆,
是
的中点,
交
于
.
![](https://img.xkw.com/dksih/QBM/2016/10/31/1573101706616832/1573101712711680/STEM/da5dea06400c4783b9c5f7d2caf7482a.png)
(Ⅰ)求证:
;
(Ⅱ)若
,点
到
的距离等于点
到
的距离的一半,求圆
的半径
.
如图,圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f2333da32638ec636fa1e69e750ca4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e262f59351803e420bf1226c95e4bba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://img.xkw.com/dksih/QBM/2016/10/31/1573101706616832/1573101712711680/STEM/da5dea06400c4783b9c5f7d2caf7482a.png)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c785dd3acc900f2df19930dcb0b816c.png)
(Ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e73c03338db66b081700f70bcf9a0989.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
您最近一年使用:0次
2016-12-04更新
|
146次组卷
|
2卷引用:2017届湖南永州市高三高考一模考试数学(理)试卷
8 . 选修4-1:几何证明选讲
如图,在
中,
,以
为直径的圆交
于点
,过点
作圆
的切线交
于点
.
![](https://img.xkw.com/dksih/QBM/2016/10/25/1573094484230144/1573094490759168/STEM/5de5fb100dd94cbd9c5021632656ede4.png)
(1)求证:
;
(2)若
,求
的大小.
如图,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd936a2405709574af0a73543d94ad9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c38d26d85081a99d51e2f686817e94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://img.xkw.com/dksih/QBM/2016/10/25/1573094484230144/1573094490759168/STEM/5de5fb100dd94cbd9c5021632656ede4.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ee170c82e3dc624dc3016443496a469.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/748aa3c2514e68c3ec55e48f4caa81f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5955fb3e36aab3514e1d23e747312a4b.png)
您最近一年使用:0次
2016-12-04更新
|
179次组卷
|
2卷引用:2017届重庆市第八中学高三理上适应性考试一数学试卷
9 . 选修4-1:几何证明选讲
如图,点
是圆
直径
的延长线上一点,
是圆
的切线,
为切点,
的平分线
与
相交于点
,与
相交于点
.
![](https://img.xkw.com/dksih/QBM/2016/12/8/1579046393077760/1579046393839616/STEM/c84ed3e0c6d9438bbf925b51ab7c0ea1.png)
(1)求
的度数;
(2)若
,证明:
.
如图,点
![](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/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0427054c47e348f35771872fd0215a8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://img.xkw.com/dksih/QBM/2016/12/8/1579046393077760/1579046393839616/STEM/c84ed3e0c6d9438bbf925b51ab7c0ea1.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dbb28736e2f6d739a732a2a0a20cabc.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12826d3f5dd6c54aaab317faad297c2a.png)
您最近一年使用:0次
2016-12-04更新
|
344次组卷
|
2卷引用:2017届三省高三上学期百校大联考数学(理)试卷
10 . 选修4-1:几何证明选讲
如图,四边形
外接于圆,
是圆周角
的角平分线,过点
的切线与
延长线交于点
,
交
于点
.
![](https://img.xkw.com/dksih/QBM/2016/9/12/1573015911538688/1573015918010368/STEM/e40e8d2e5f3446c2aeb156a47188a259.png)
(1)求证:
;
(2)若
是圆的直径,
,求
的长.
如图,四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd777f9452cb8b56d8a0d3b07d15c19f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://img.xkw.com/dksih/QBM/2016/9/12/1573015911538688/1573015918010368/STEM/e40e8d2e5f3446c2aeb156a47188a259.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a73c8a92b36b72cc4441fd0a9013f841.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f03dab955d3953261e1f3f437f6128f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次