特例感知:
如图1,在等边三角形
中,
是
延长线上一点,且
,以
为边在上方作等边三角形
,连接
,过点
作
,过点
作
,交于点
,连接
.
![](https://img.xkw.com/dksih/QBM/2023/4/18/3218997599191040/3219891060064256/STEM/7253af4fcc18482e9f1a3254b815a10e.png?resizew=542)
(1)试判断
和
的数量关系,并说明理由.
猜想论证:
(2)将
绕点
按顺时针方向旋转一定角度,其余操作不变,则
和
的数量关系是否仍然成立,请仅就图2的情形说明理由.
拓展延伸:
(3)将如图1所示的
绕点C按逆时针方向旋转
,其余操作不变.若
,当
是直角三角形时,请直接写出α的值.
如图1,在等边三角形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caedb55e1410c5083c2a8645008527a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10fc7991ea17d54ff5f4445ac5699463.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/498c6ba8c5d560eef36044a53c7057ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37277bc0191d90453005ef69562f552b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://img.xkw.com/dksih/QBM/2023/4/18/3218997599191040/3219891060064256/STEM/7253af4fcc18482e9f1a3254b815a10e.png?resizew=542)
(1)试判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
猜想论证:
(2)将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d631f45bc652539853f236952afa5bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
拓展延伸:
(3)将如图1所示的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d631f45bc652539853f236952afa5bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b40aa8d2482d698ebef69cf225f99f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc2a229465c6e60af49839afd5ffa885.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/004104bafb5f30338123d4ea2b7fedde.png)
更新时间:2023-04-19 15:08:02
|
相似题推荐
解答题-证明题
|
较难
(0.4)
【推荐1】在
中,
,
.点
在线段
上,以
,
为边作正方形
,
与
,
的交点分别为
,
.
(1)求证:
;
(2)若点
为
的中点,求
的长;
(3)当
为等腰三角形时,求
的长.
![](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/cd0763b031b7e6b6d87ce3554ac482d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9abaeba15f3abdd877bc701af52c5cd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b9d54cbbf601f4583659771eb534997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.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/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/19/5ced9a12-270e-44c6-815b-44596cc62213.png?resizew=207)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f23da5bc0c9e2acd1f120e00be7298c.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
(3)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/029ad83f1a3262048cba0e650b63e929.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
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解答题-证明题
|
较难
(0.4)
【推荐2】(1)如图1,△ABC中,
,
是
的中线,且
,求
的取值范围;
(2)如图2,
和
是两个全等的三角形,
,且
,将
绕点C顺时针旋转
,如图3,点A的对应点是E,点B的对应点为F,取
的中点M,连接
,求证:
;
(3)在(2)的条件下,当
时,则
______(直接填结果).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f08273d339dc5ddbb89aa67bb8205e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0d5a2cd05e4476fc72271e8fdb59a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
(2)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/681a4c0e1bba3332b0dde5ce55d30e2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59281d3136f2c67c078d98842171224d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0b641c734c0c23261e1b3a18c39fa5e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1571c3b8485cf475118d340cdac2aa65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56ac25f293bd331a3a0a8c72e9e79817.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c3bcf92cdcb0b7159cc8c9ded2f0101.png)
(3)在(2)的条件下,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/061da3a8d2429e9f2459418b7e6acdfd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9251dff989f7d60db751b73033dee269.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/24/e72c1b87-6776-4715-b8f3-1416a979b8a9.png?resizew=589)
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解答题-作图题
|
较难
(0.4)
【推荐1】如图,等边
中,点P是
边上一点,作点C关于直线
的对称点D,连接
,作
于点E.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/10/44dc1f09-6965-49fd-8735-8cbd0bd3d088.png?resizew=318)
(1)若
,依题意补全图1,并直接写出
的度数;
(2)如图2,若
,
①求证:
;
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/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c251ab32593beafa54391230b5721d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c51c25b65a37b676ae3c3b71c29f9b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/10/44dc1f09-6965-49fd-8735-8cbd0bd3d088.png?resizew=318)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68084afe32c3dbeb34106336aeeebacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/727ad3e630a224303d6d3b8ad5c114ba.png)
(2)如图2,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75ef6cc5ea45d53fbf5de559870d499b.png)
①求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55c12e1207a839d28a30b0ff622666c4.png)
②用等式表示线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56cd20bf00d8cd6cb9fed1d308a24386.png)
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解答题-证明题
|
较难
(0.4)
解题方法
【推荐2】综合与实践
问题情境
数学活动课上,老师让同学们以“三角形平移与旋转”为主题开展数学活动,△ACD和△BCE是两个等边三角形纸片,其中,AC=5cm,BC=2cm.
解决问题
(1)勤奋小组将△ACD和△BCE按图1所示的方式摆放(点A,C,B在同一条直线上),连接AE,BD.发现AE=DB,请你给予证明;
(2)如图2,创新小组在勤奋小组的基础上继续探究,将△BCE绕着点C逆时针方向旋转,当点E恰好落在CD边上时,求△ABC的面积;
拓展延伸
(3)如图3,缜密小组在创新小组的基础上,提出一个问题:将△BCE沿CD方向平移acm,得到B'C'E',连接AB',B'C,当△AB'C恰好是以AB'为斜边的直角三角形时,求a的值.请你直接写出a的值.
问题情境
数学活动课上,老师让同学们以“三角形平移与旋转”为主题开展数学活动,△ACD和△BCE是两个等边三角形纸片,其中,AC=5cm,BC=2cm.
解决问题
(1)勤奋小组将△ACD和△BCE按图1所示的方式摆放(点A,C,B在同一条直线上),连接AE,BD.发现AE=DB,请你给予证明;
(2)如图2,创新小组在勤奋小组的基础上继续探究,将△BCE绕着点C逆时针方向旋转,当点E恰好落在CD边上时,求△ABC的面积;
拓展延伸
(3)如图3,缜密小组在创新小组的基础上,提出一个问题:将△BCE沿CD方向平移acm,得到B'C'E',连接AB',B'C,当△AB'C恰好是以AB'为斜边的直角三角形时,求a的值.请你直接写出a的值.
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
名校
【推荐3】如图1,在平面直角坐标系
中,直线
分别与
轴正半轴、
轴正半轴交于点
、
,且
,
,等边
的顶点
与原点
重合,
边落在
轴的正半轴上,点
恰好落在线段
上,如图
,将等边
从图
的位置沿
轴正方向以
的速度平移,边
,
分别与线段
交于点
、
,在
平移的同时,点
从
的顶点
出发,以
的速度沿折线
运动,当点
达到点
时,点
停止运动,
也随之停止平移.设
平移时间为
(
),
的面积为
(
).
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/9/e0720b58-aa6f-40bc-be4d-7787404c8b59.png?resizew=365)
(1)等边
的边长是______;
(2)当点
在线段
上运动时,直接写出
与
的函数关系式______;
(3)点
沿折线
运动的过程中,是否在某一时刻,使
为等腰三角形?若存在,直接写出此时
值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f2beb91f10d2d8f2aa0dcc3f5cd1598.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa29fe6cd9eb51c184f6299d437375cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53e9c044a39b53b340fc318c3eb12130.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3b2da1e9f76ffde527bf35de7060456.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa29fe6cd9eb51c184f6299d437375cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f051275aa34c90fd6957973f6640753.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1a9c6a736e6eac98a676fa3232db5a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa29fe6cd9eb51c184f6299d437375cb.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/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/171e02f78e30ca17469c7ec007dd8db3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1da0304251a6a0966cd5238660dfa9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](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/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8c1468cf3bc2bbc5bee776b882f42eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91b51d3992644d37dc71c9b5a97d515c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88ce13774b09ff2edddaf21a072cf60a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/9/e0720b58-aa6f-40bc-be4d-7787404c8b59.png?resizew=365)
(1)等边
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41ff8c8d239cc12ddc3a899e9f054aa9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
(3)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1da0304251a6a0966cd5238660dfa9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91b51d3992644d37dc71c9b5a97d515c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
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