正方形
的边长为4,点E在
上,点F在
上,且
,
与F交于G点.
![](https://img.xkw.com/dksih/QBM/2022/10/15/3088061615194112/3090973348241408/STEM/d3d23f76fa8845cea2f336deb29dc750.png?resizew=540)
(1)如图1,求证:①
,②
.
(2)连接
并延长交
于点H.
①若点E为
的中点(如图2),求BH的长;
②当点E在
的边上滑动(不与B、C重合)时,直接写出
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d4546153ab4353af86c0023f2c2092.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://img.xkw.com/dksih/QBM/2022/10/15/3088061615194112/3090973348241408/STEM/d3d23f76fa8845cea2f336deb29dc750.png?resizew=540)
(1)如图1,求证:①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b51cee4392cf5d4086b2e6c5b3b98341.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54fe3df60bb876adde6da340b692e4e1.png)
(2)连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
①若点E为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
②当点E在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
更新时间:2022-10-19 11:44:17
|
相似题推荐
解答题-证明题
|
较难
(0.4)
【推荐1】如图①,在等腰
中,
,
,
为线段
上一点,以
为半径作
交
于点
,连接
、
,线段
、
、
的中点分别为
、
、
.
(1)试探究
是什么特殊三角形?说明理由;
(2)将
绕点
逆时针方向旋转到图②的位置,上述结论是否成立?并证明结论;
(3)若
,把
绕点
在平面内自由旋转,求
的面积y的最大值与最小值的差.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5b352fa3e781df195ceccca90c3932a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59a0c9ad9c9558330fd78bb6f7a3ecbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3825ccc273ef9a672a606432d165b866.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2c3d2cba96f6f03520c0b3f6e4da03e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/13/2b32cca6-029a-49d7-8a77-21ee70891234.png?resizew=443)
(1)试探究
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/999c42a021bdc576f097246b9e64d986.png)
(2)将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea1f0417d8269f01d8e0bc1a8756e2ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fe96ad0a14cc36f403353bc324ed82d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea1f0417d8269f01d8e0bc1a8756e2ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/999c42a021bdc576f097246b9e64d986.png)
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
【推荐2】如图,在等腰
中,
,
,点D在
边上由C向B匀速运动(D不与B、C重合),匀速运动速度为
,连接
,作
,
交线段
于点E.
(1)在运动过程中,
逐渐变 (填“大”或“小”);D点运动到图1位置时,
,则
.
(2)点D运动3s后到达图2位置,则CD= .此时
和
是否全等,请说明理由.
(3)在点D运动过程中,
的形状也在变化,判断当
是等腰三角形时,
等于多少度?(请直接写出结果)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6478c34483a1ab290a8d84982c9f608.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d3c9ce32b721995f355eea411340e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b9174c3b1324cf81098e42e0480bcc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5f374024260b8d0083f41c2bb825b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d97dc3b752832906de41447bb58a341.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/20/2ac241b9-9d9d-4460-92c0-d33c5f01a5c3.png?resizew=434)
(1)在运动过程中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60b47abcacc10f90489c0d52a9e269ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ce784401cd464ee64cf9933a92f5608.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/801ea0313c20b2905edcda4fd3f83eb6.png)
(2)点D运动3s后到达图2位置,则CD= .此时
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a0acc93490a6a784eb62201d93dd93d.png)
(3)在点D运动过程中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60b47abcacc10f90489c0d52a9e269ab.png)
您最近一年使用:0次
解答题-作图题
|
较难
(0.4)
名校
【推荐3】【问题情境】
如图1,四边形
和四边形
都为正方形,
,点E在
的延长线上,点G在
的延长线上,分别连接对角线
,
,
.将正方形
从图1的位置开始绕点C顺时针旋转,设旋转角为
(
)
(1)小斌画出了旋转角
时的情形(如图2),连接
后,小斌发现四边形
是平行四边形,请帮他证明这一结论;
(2)小亮画出了旋转角
时的某一情形(如图3),连接
、
,写出线段
、
的关系: ______.
(3)如图4,小颖在正方形
绕点G旋转过程中(
),连接
、
,请你直接写出当
为等腰三角形时
的值.
如图1,四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b1f13007c6d134c50004c62dc240707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e55e398e8520d8a36fb5a625a085b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa80cfd38f59e5cbbb30628d03113689.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b1f13007c6d134c50004c62dc240707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/165654f64dcc343721d53b85cac3cf86.png)
【自主探究】
(1)小斌画出了旋转角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c69a23d106fd34aa17b22e9c9a8de36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9365798257869ab59ef656d3a0679553.png)
(2)小亮画出了旋转角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f64f0db3ac82ba45e8272f63dcc65a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06e322e0c87479bba874db9ae9ba36b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06e322e0c87479bba874db9ae9ba36b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
【拓展延伸】
(3)如图4,小颖在正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b1f13007c6d134c50004c62dc240707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/165654f64dcc343721d53b85cac3cf86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06e322e0c87479bba874db9ae9ba36b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d20227c155003de7163d407daf0a5e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daecbf44f4f4394f10fc9550dcac0abe.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐1】如图,在正方形
中,P是直线
上的一点,连接
,过点
作
,交直线
于点E,连接
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/13/d7040649-772b-4d43-9ee1-251be94312b4.png?resizew=271)
(1)当点P在线段
上时,如图①,求证:
;
(2)当点P在直线
上移动时,位置如图②、图③所示,线段
,
与
之间又有怎样的数量关系?请直接写出你的猜想,不需证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a82abf041a3135fc1eb413d669a0e9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/13/d7040649-772b-4d43-9ee1-251be94312b4.png?resizew=271)
(1)当点P在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d577d13aef6f36e8bb62266dc9a298de.png)
(2)当点P在直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
您最近一年使用:0次
【推荐2】已知正方形ABCD与正方形AEFG,正方形AEFG绕点A旋转一周.
(1)如图①,连接BG、CF,求
的值;
(2)当正方形AEFG旋转至图②位置时,连接CF、BE,分别取CF、BE的中点M、N,连接MN、试探究:MN与BE的关系,并说明理由;
(3)连接BE、BF,分别取BE、BF的中点N、Q,连接QN,AE=6,请直接写出线段QN扫过的面积.
(1)如图①,连接BG、CF,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9af4ea989fa0a89c7fef51255a92116b.png)
(2)当正方形AEFG旋转至图②位置时,连接CF、BE,分别取CF、BE的中点M、N,连接MN、试探究:MN与BE的关系,并说明理由;
(3)连接BE、BF,分别取BE、BF的中点N、Q,连接QN,AE=6,请直接写出线段QN扫过的面积.
![](https://img.xkw.com/dksih/QBM/2021/6/24/2749783582916608/2749859093340160/STEM/b224f482-09c2-4afc-b5a7-3ce825c43694.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
名校
【推荐1】如图,点P为正方形
的边
上的一个动点,连接
,点D与点E关于直线
对称,连接
,射线
与射线
交于点
,连接
.
时,求
的度数;
(2)i)点P在运动过程中,
的度数是否发生变化?如果不变,请求出它的度数,如果改变,请说明理由;
ii)求证:
;
(3)若
,点P从点C运动到点B时,求点F运动路径的长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccaee8f228ff24e7c89879bb5b999cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79633ecd19f74e9137db734691571e35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13a2e6494cf8d2dff0746a9bb72cef43.png)
(2)i)点P在运动过程中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13a2e6494cf8d2dff0746a9bb72cef43.png)
ii)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32326495961bdc6376b9cb350cc46453.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6834ac70927ae08d7d36a1922403c9e.png)
您最近一年使用:0次
解答题-证明题
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名校
【推荐2】几何问题中需建构模型去研究图形中元素之间的关系…
在
中,P是
上一点,点E 在直线
的上方,连接
,
,
,探究下列问题:
(1)如图①,
,
①连接
,求证:
;
②
与
满足的数量关系为 ;
【运用模型】
(2)已知
,D 是
的中点,且
,
①如图②,若P是
的中点,连接
,求证:
;
②若
,当点P在
上运动时,点E的位置随点P的位置的变化而变化,直接写出
的长的最小值.
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f541f7ae7c39082d202efd28805c54e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
(1)如图①,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baa6c6ccf231d0001bdaef430154edfd.png)
①连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3925cba1c8fce73c939b1ce3ae56c6b.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6282292819434a8905a212427613fd85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
【运用模型】
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a937f7e411921336df800a30dead46e.png)
①如图②,若P是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c436f108fd4921dae15ecff19270237e.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6beab6735f6680f0c5946afe1ec46dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐1】综合与实践
在一节数学课上,张老师提出了这样一个问题:如图1,在等腰直角三角形
中,
,D是边
上一动点(不与点B重合),
,
,
交
于点F.猜想线段
,
之间的数量关系并说明理由.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/17/c70a2241-ff88-4304-b36a-bf234b9b2d2c.png?resizew=394)
小聪与同桌小明讨论后,仍不得其解,张老师给出提示:“数学中常通过把一个问题特殊化来找到解题思路.”两人茅塞顿开,于是进行了如下讨论,请仔细阅读,并完成相应的任务.
任务一:如图2,猜想线段
之间的数量关系为_________.
任务二:通过阅读上述讨论,请在小聪与小明的方法中选择一种,就图1中的情形判断线段
之间的数量关系,并给出证明.
任务三:若
,其他条件不变,当
是直角三角形时,直接写出
的长.
在一节数学课上,张老师提出了这样一个问题:如图1,在等腰直角三角形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f65dfd32cc6ff4d10f7992d84915043f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c182a9d9fd0a7023b710cd671d9468e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/17/c70a2241-ff88-4304-b36a-bf234b9b2d2c.png?resizew=394)
小聪与同桌小明讨论后,仍不得其解,张老师给出提示:“数学中常通过把一个问题特殊化来找到解题思路.”两人茅塞顿开,于是进行了如下讨论,请仔细阅读,并完成相应的任务.
小聪:已知点D是动点,因此可以将点D移动到一个特殊的位置.当点D与点C重合时,如图2所示.此时可以分别延长![]() ![]() ![]() ![]() ![]() ![]() ![]() 小明:对于图2,我有不同的证明方法,过点F分别作 ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf22927eb6819a02978ef0c6b101f6f5.png)
任务二:通过阅读上述讨论,请在小聪与小明的方法中选择一种,就图1中的情形判断线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf22927eb6819a02978ef0c6b101f6f5.png)
任务三:若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/441dec590b47adc3678a291a3ec89a4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐2】【探索发现】
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/17/80d57bbf-2614-4b22-ac84-eef0956b5ddc.png?resizew=713)
(1)如图1,在四边形ABCD中,
,对角线AC、BD相交于M,则
成立吗?小丽是这样证明的.
证明:过点A作
于点E,
于点F,
,
,
∵
,
∴![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d52400a576b6e4b742ff0731cb8198b.png)
∴
,
∴![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41d1a3eb4ebfbef18d13dc58b19ea60.png)
【类比应用】
(2)如图2,对于四边形ABCD中,对角线AC、BD相交于M,则
的结论是否成立?请写出证明过程.
【拓展延伸】
(3)在图(3)的情形下,
,则
_________
(4)在图(4)的情形下,
,则
_________
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/17/80d57bbf-2614-4b22-ac84-eef0956b5ddc.png?resizew=713)
(1)如图1,在四边形ABCD中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41d1a3eb4ebfbef18d13dc58b19ea60.png)
证明:过点A作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c51c25b65a37b676ae3c3b71c29f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aac18b0388014ae20b2add2975ef56aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f85bbe0b4b29a0aee8659bafe5eba917.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e4a2a59bda92417dd9a5d8e1d082009.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1949014bf5798c205352401a13527c8.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d52400a576b6e4b742ff0731cb8198b.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56aa163cd358116337f5a8545db57dcb.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41d1a3eb4ebfbef18d13dc58b19ea60.png)
【类比应用】
(2)如图2,对于四边形ABCD中,对角线AC、BD相交于M,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41d1a3eb4ebfbef18d13dc58b19ea60.png)
【拓展延伸】
(3)在图(3)的情形下,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/658dccee914e64f1bc7f1a0639ffdf81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cc2564dc031bc27dbd39197b4405989.png)
(4)在图(4)的情形下,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63eb9b33c5af9d49608b3995aeb11b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edde71ad25228854c0138b6bead7fb05.png)
您最近一年使用:0次