名校
解题方法
1 . 在△ABC中,AC=BC,∠ACB=α,点D为直线BC上一动点,过点D作DF∥AC交直线AB于点F,将AD绕点D顺时针旋转α得到ED,ED交直线AB于点O,连接BE.
![](https://img.xkw.com/dksih/QBM/2020/6/28/2494212005036032/2494862985076736/STEM/6c55a3c0693d452d833cb9f9f1fb97c1.png?resizew=425)
(1)问题发现:
如图1,α=90°,点D在边BC上,猜想:
①AF与BE的数量关系是 ;
②∠ABE= 度.
(2)拓展探究:
如图2,0°<α<90°,点D在边BC上,请判断AF与BE的数量关系及∠ABE的度数,并给予证明.
(3)解决问题
如图3,90°<α<180°,点D在射线BC上,且BD=3CD,若AB=8,请直接写出BE的长.
![](https://img.xkw.com/dksih/QBM/2020/6/28/2494212005036032/2494862985076736/STEM/6c55a3c0693d452d833cb9f9f1fb97c1.png?resizew=425)
(1)问题发现:
如图1,α=90°,点D在边BC上,猜想:
①AF与BE的数量关系是 ;
②∠ABE= 度.
(2)拓展探究:
如图2,0°<α<90°,点D在边BC上,请判断AF与BE的数量关系及∠ABE的度数,并给予证明.
(3)解决问题
如图3,90°<α<180°,点D在射线BC上,且BD=3CD,若AB=8,请直接写出BE的长.
您最近一年使用:0次
2020-06-29更新
|
698次组卷
|
3卷引用:2020年河南省南阳市卧龙区中考数学一模试题
2020年河南省南阳市卧龙区中考数学一模试题(已下线)专题16 以矩形为基础的图形的旋转变换问题(九年级上重点突破)北师大版辽宁省沈阳市第一三四中学2021-2022学年九年级上学期11月月考数学试题
2 . 已知四边形
中,
,
分别是
,
边上的点,
与
交于点
,令
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/5/25/59be97f6-b291-415d-85cd-70adb5a5bcd6.png?resizew=485)
特例解析:如图1,若四边形
是矩形,且
,求证:
;
类比探究:如图2,若四边形
是平行四边形,当
与
满足什么关系时,
仍然成立?并证明你的结论;
拓展延伸:如图3,在(2)的条件下,若
,
,
,
,求
的长.
![](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/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aca6ad6a8cee27ee318c1a4fa443b2e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/5/25/59be97f6-b291-415d-85cd-70adb5a5bcd6.png?resizew=485)
特例解析:如图1,若四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1f87b02b744534ae1ed700d21fcceb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c61ed1ed1bfd0fea288d61425f1867db.png)
类比探究:如图2,若四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/febc9a89d0d1c97b88c0f4acd32b4e67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16a8e30f70325b5b14851b9377107ab8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c61ed1ed1bfd0fea288d61425f1867db.png)
拓展延伸:如图3,在(2)的条件下,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8a120e186030ca3ac6987ce80b9fb10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecf7679c8b4b1e442ce4286d4b0e9c32.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff5121ba0251bba181fc1880368e5e7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd32d2db65c6c30f0981cf6b21ab94bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
您最近一年使用:0次
2020-06-27更新
|
286次组卷
|
2卷引用:2020年湖北省襄阳市樊城区九年级中考二模数学试题
2019九年级·河南·专题练习
解题方法
3 . 在
中,
,
,点P是平面内不与点A,C重合的任意一点,连接CP,将线段CP绕点P旋转
得到线段DP,连结AP,CD,BD.
(1)观察猜想:如图1,当
时,线段CP绕点P顺时针旋转
得到线段DP,则
的值是______,直线AP与BD相交所成的较小角的度数是______;
(2)类比探究:如图2,当
时,线段CP绕点P顺时针旋转
得到线段
请直接写出AP与BD相交所成的较小角的度数,并说明
与
相似,求出
的值;
(3)拓展延伸:当
时,且点P到点C的距离为
,线段CP绕点P逆时针旋转
得到线段DP,若点A,C,P在一条直线上时,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ab41054fa9ce51b68e78d9c0cf398d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e95a71bf1a32aacf7ac583dbf2a8e4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
(1)观察猜想:如图1,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc97b284d8756186fbe9bcb4038adddf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/256508192d06b91ef174d041eb08a5f5.png)
(2)类比探究:如图2,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecd39d1aa24e873206cdfc7872043c33.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75b624af009243052faf6a2ea5cf223a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b506b0941433a6a5d5387d0ec95596ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65fbd5e25a4186845a78a9aadd8d4582.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/256508192d06b91ef174d041eb08a5f5.png)
(3)拓展延伸:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecd39d1aa24e873206cdfc7872043c33.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d38f759f2a496182e5bb5b500bbacfa6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/256508192d06b91ef174d041eb08a5f5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/28/29af3160-e090-47e6-847a-51f533b86555.png?resizew=626)
您最近一年使用:0次
2021-04-11更新
|
348次组卷
|
3卷引用:【万唯原创】河南省中考数学-河南缺题-类比探究上
名校
4 . 如图1,菱形ABCD与菱形GECF的顶点C重合,点G在对角线AC上,且∠BCD=∠ECF=60°,
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/91395941-41ae-4b78-9e76-45e5086f60d0.png)
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/e6c6e7c6-c139-42ad-a35f-c4c955f547be.png)
(1)问题发现
的值为_______;
(2)探究与证明:将菱形GECF绕点C按顺时针方向旋转α角(0°<α<60°),如图2所示,试探究线段AG与BE之间的数量关系,并说明理由;
(3)拓展与运用:菱形GECF在旋转过程中,当点A,G,F三点在一条直线上时,如图3所示连接CG并延长,交AD于点H,若CE=2,GH=
,则AH的长为_______.
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/91395941-41ae-4b78-9e76-45e5086f60d0.png)
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/e6c6e7c6-c139-42ad-a35f-c4c955f547be.png)
(1)问题发现
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45ec2c1bca9d89d16df525a45408aa76.png)
(2)探究与证明:将菱形GECF绕点C按顺时针方向旋转α角(0°<α<60°),如图2所示,试探究线段AG与BE之间的数量关系,并说明理由;
(3)拓展与运用:菱形GECF在旋转过程中,当点A,G,F三点在一条直线上时,如图3所示连接CG并延长,交AD于点H,若CE=2,GH=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
您最近一年使用:0次
2020-09-26更新
|
337次组卷
|
8卷引用:【校级联考】河南省周口市鹿邑县2019届九年级中考第一次模拟数学试题
5 . 定义:如果一个三角形一条边上的高与这条边的比值是3:5,那么称这个三角形为“准黄金”三角形,这条边就叫做这个三角形的“金底”.
【概念感知】
(1)如图1,在
中,
,
,
,试判断
是否是“准黄金”三角形,请说明理由.
![](https://img.xkw.com/dksih/QBM/2020/5/18/2465591574716416/2466226873851904/STEM/812087410d494db0b783c0817406775c.png?resizew=312)
【问题探究】
(2)如图2,
是“准黄金”三角形,BC是“金底”,把
沿BC翻折得到
,连AB接AD交BC的延长线于点E,若点C恰好是
的重心,求
的值.
【拓展提升】
(3)如图3,
,且直线
与
之间的距离为3,“准黄金”
的“金底”BC在直线
上,点A在直线
上.
,若
是钝角,将
绕点
按顺时针方向旋转
得到
,线段
交
于点D.
①当
时,则
_________;
②如图4,当点B落在直线
上时,求
的值.
【概念感知】
(1)如图1,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd0763b031b7e6b6d87ce3554ac482d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ebb33adb2310a6e03918761e68204a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/392b9e1a179a6676362679354a9e7e51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://img.xkw.com/dksih/QBM/2020/5/18/2465591574716416/2466226873851904/STEM/812087410d494db0b783c0817406775c.png?resizew=312)
【问题探究】
(2)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0005e1ef60f6ddc5f9a83e3de1ef3b2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2465ee1fec12351943f15055dfd6ec73.png)
【拓展提升】
(3)如图3,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1095c036b49c3327baaa2c3c7f746134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9801a8426c3c1c8b7db1b54d07f4315f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aeb1aa7bc4a01962fc1297f17fa9128f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b185184dc2dc3894a0313fd13f26a59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eb97aff0960e2640314888a38e7169c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
①当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6c96cb3ac8290e09c55d4eb336a8608.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1ec5d678ec42846e1d28301e3bfd4be.png)
②如图4,当点B落在直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61f9215613b7b05217ed77268c238391.png)
![](https://img.xkw.com/dksih/QBM/2020/5/18/2465591574716416/2466226873851904/STEM/8ca234de8a464e40a1d7e1b5cac6d02a.png?resizew=404)
您最近一年使用:0次
2020-05-19更新
|
790次组卷
|
3卷引用:江西省抚州市金溪县第一中学2019-2020学年九年级下学期统一测试(一)数学试题
6 . (1)如图①,在四边形
中,
,点
在
边上,
,求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ec2ec6cf30c455d67c34e27fe4957c.png)
(2)探究:如图②,在四边形
中,点
在
边上,当
时,求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ec2ec6cf30c455d67c34e27fe4957c.png)
(3)拓展:如图③,在
中,点
是边
的中点,点
分别在边
上,若
,求
的长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71069b7ae2205c2f51022bd67e371772.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ec2ec6cf30c455d67c34e27fe4957c.png)
(2)探究:如图②,在四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/516bcdc180f55d0c66fe19c0712dcaef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ec2ec6cf30c455d67c34e27fe4957c.png)
(3)拓展:如图③,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34ff9d4fdd0d176042505b7aac016852.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.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/7dec2ca6438c82b43f746057d8129885.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d24f91e93b8b15e9c0ff4923e5015313.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/14/b2917860-4786-4ff2-bb10-11dd13a843e6.png?resizew=500)
您最近一年使用:0次
2020-11-23更新
|
164次组卷
|
2卷引用:四川博瑞特外国语学校2020-2021学年九年级上学期期中数学试题
名校
7 . 如图1,已知点G在正方形ABCD的对角线AC上,GE⊥BC,垂足为点E,GF⊥CD,垂足为点F.
(1)证明:四边形CEGF是正方形;
(2)探究与证明:
将正方形CEGF绕点C顺时针方向旋转α角(0°<α<45°),如图2所示,试探究线段AG与BE之间的数量关系,并说明理由;
(3)拓展与运用:
正方形CEGF绕点C顺时针方向旋转α角(0°<α<45°),如图3所示,当B,E,F三点在一条直线上时,延长CG交AD于点H,若AG=6,GH=2
,求BC的长.
(1)证明:四边形CEGF是正方形;
(2)探究与证明:
将正方形CEGF绕点C顺时针方向旋转α角(0°<α<45°),如图2所示,试探究线段AG与BE之间的数量关系,并说明理由;
(3)拓展与运用:
正方形CEGF绕点C顺时针方向旋转α角(0°<α<45°),如图3所示,当B,E,F三点在一条直线上时,延长CG交AD于点H,若AG=6,GH=2
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://img.xkw.com/dksih/QBM/2020/4/26/2449621556232192/2449703899561984/STEM/6fb4fc3b2783487d85eaebe77948f169.png?resizew=421)
您最近一年使用:0次
2020-04-26更新
|
353次组卷
|
2卷引用:2020年四川省成都市树德中学九年级二诊数学模拟试题
8 . (1)初步探究:如图(1),点
、
分别在正方形
边
、
上,
于点
,小芳看到该图后,发现
,这是因为
和
都是
的余角,就会由______判定得出______≌______.
(2)类比发现:小芳进一步思考,如果四边形
是矩形,如图,且
于点
,她发现
,请你替她完成证明.
(3)拓展延伸:如图(3),若四边形
是平行四边形,试探究:当
与
满足什么关系时,使得
成立?并证明你的结论.
![](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/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1f87b02b744534ae1ed700d21fcceb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1db2c0955e5a5be47faf855bca738a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1428d4a45e569bc6e39005ea3c9c8ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6fc8bfdbf2a7e4ab5ef262b20611785.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/836ea820cf3732508cdd332ceb9395ce.png)
(2)类比发现:小芳进一步思考,如果四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1f87b02b744534ae1ed700d21fcceb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2753a0194119801844add1fbbe7745b.png)
(3)拓展延伸:如图(3),若四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/febc9a89d0d1c97b88c0f4acd32b4e67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9bebe23a3e351436edec2f6b4312fee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2753a0194119801844add1fbbe7745b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/31/899aa5a5-818e-432e-8fb0-a982e7f2f060.png?resizew=570)
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9 . 综合与实践
如图①,在中
中,
,
,
,过点
作
于
,将
绕点
逆时针方向旋转,得到
,连接
,
,记旋转角为
.
(1)问题发现
如图②,当
时,
__________;如图③,当
时,
__________.
(2)拓展探究
试判断:当
时,
的大小有无变化?请仅就图④的情形给出证明.
(3)问题解决
如图⑤,当
绕点
逆时针旋转至点
落在边
上时,求线段
的长.
如图①,在中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8a7b5adfcac0f46a4cd19da4ebb4a2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f8eeeea1c9652cacce976f8129cf520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b757f0c42ae5c9a2d6a4b19e5877b27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f15ba851a0f65c271ec774095516f07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3918c6df1525b2836a3e19735a2a33d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/020ebe1219437129358b986eb9e70bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4336253885d52e43ba6eaa297ea847b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
(1)问题发现
如图②,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33ac762a2899a58faa0d3ab44f1281fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fe6341a1a556de549a9e5365888fc64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ddd284be60584dfae454b1a125468947.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fe6341a1a556de549a9e5365888fc64.png)
(2)拓展探究
试判断:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27b4160b8913466f0304a96ce7c628bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa981ec8ebcd0203e249f125f849a6e.png)
(3)问题解决
如图⑤,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f15ba851a0f65c271ec774095516f07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4c8a9c4957431681ddfc77895a88508.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/020ebe1219437129358b986eb9e70bbf.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/15/8393632f-a25e-4320-9f27-93b6ca6c289d.png?resizew=593)
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名校
解题方法
10 . 问题背景
在
中,
,
,
,点
、
分别是边
、
上的动点,设
,
两点之间的距离为
,
、
两点之间的距离为
.
初步思考
(1)如图1,过点
作
的垂线,垂足为
,连结
、
.当
时,
________;
深入探究
(2)如图2,若
于
,以
,
为邻边作平行四边形
,当
时,是否存在
,使得平行四边形
的顶点
恰好落在
的边上?若存在,请求出
的值,若不存在,请说明理由.
![](https://img.xkw.com/dksih/QBM/2020/12/29/2624371663798272/2625872083304448/STEM/432ee606-e870-4e23-8e86-cdb55f29ccf6.png?resizew=372)
拓展延伸
(3)如图3,连接
、
交于点
,若
,且满足
,判断
是否为定值?若是,请求出
的值;若不是,请说明理由.
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c8807117d0d649419fdda04c531cdc0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82b74e2b6dae540571fdd509c4e966b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b939af5ba06e279cce39396aaf0fae06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
初步思考
(1)如图1,过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bab17635a999236e8d2e35017a208d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7c57b07f75e97d9f84718bd495ebcf4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbb388a36bd5caaa51b7e3c898e3c906.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ec0618ae3a4fde6d6220010af229b9a.png)
深入探究
(2)如图2,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32c38dfd14dde969702dff97ef2270f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bab17635a999236e8d2e35017a208d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7c57b07f75e97d9f84718bd495ebcf4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bf6ff8ab059df730af48806b32edfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39cc033406da2cdd342308972c6701f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bf6ff8ab059df730af48806b32edfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://img.xkw.com/dksih/QBM/2020/12/29/2624371663798272/2625872083304448/STEM/432ee606-e870-4e23-8e86-cdb55f29ccf6.png?resizew=372)
拓展延伸
(3)如图3,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef667b04a6656e8fd171a8743a27bdd1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f173a03f2b6749db9f44f43efc79a15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://img.xkw.com/dksih/QBM/2020/12/29/2624371663798272/2625872083304448/STEM/8338454a-a216-4cc8-801d-5b5f973fa445.png?resizew=214)
您最近一年使用:0次