问题:如图(1),在
中,
,试探究
满足的等量关系.
![](https://img.xkw.com/dksih/QBM/2021/4/9/2696380659908608/2696668835028992/STEM/ff8f4e12-a76c-40af-ad46-bad0b440cf88.png?resizew=349)
[探究发现]小聪同学利用图形变换,将
绕点
逆时针旋转
得到
,连接
,由已知条件易得
.
根据“边角边”可证
______,得
.
在
中,由______定理,可得
,由
,可得
之间的等量关系是______.
[实践运用]
(1)如图(2),在正方形
中,
的顶点
分别在
边上,高
与正方形的边长相等,
①求
的度数;
②连接
,分别交
于点
,若
,运用小聪同学探究的结论,求正方形的边长及
的长.
(2)在(1)的条件下,请继续探究
与
的面积的数量关系,写出结论并加以证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f76899b3a0bfbbdae7cb1148ad4bf018.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da36cc34fcaa38aad06cd7cf7d61b19a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77f15c3af8a6d4e03bffdddf65cb8f9d.png)
![](https://img.xkw.com/dksih/QBM/2021/4/9/2696380659908608/2696668835028992/STEM/ff8f4e12-a76c-40af-ad46-bad0b440cf88.png?resizew=349)
[探究发现]小聪同学利用图形变换,将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a4a514e2e338c6fa31c9938624a4a71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5cbeac5798a155ac8649f1236fe451d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589786dd7c3a2679c3230b671cd232d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91938551094c8ee1f2280dd20bf7a06a.png)
根据“边角边”可证
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39863a0466c9df2ff8c41a498773b732.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30cad9c918d03cc2a4076d307ea03a71.png)
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d3538ae7c2be50eabaed4addf9f13cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d1e2574ae574472a5c5f98b88dfdba9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34f9964e2164838720ac7a3189e63f65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77f15c3af8a6d4e03bffdddf65cb8f9d.png)
[实践运用]
(1)如图(2),在正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c105d6ba18fbb0581fb982175e2eac9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cf9b288c48c73463a2f214f02b6952a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a20cb2c77ea29b6eabbc477bc3743859.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77a7e4a6765ce78b05ee97764771e01f.png)
①求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e31edc5b71c488ca9942d70d9298f01.png)
②连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de9f075d2558b7dce0eb91148de84fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6670479a0083dd2dfd5ad55b47b1ab6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86646f41d02f37bf7480b39a0107ccb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
(2)在(1)的条件下,请继续探究
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98013a5042685a1db94249e70c62c09a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c105d6ba18fbb0581fb982175e2eac9.png)
19-20八年级下·浙江·阶段练习 查看更多[1]
(已下线)【新东方】义乌初中数学初二下【00028】
更新时间:2021-04-10 09:29:42
|
相似题推荐
解答题-证明题
|
较难
(0.4)
【推荐1】如图1,正方形
的对角线
相交于点O,在线段
上各取一点F,E使得
,连接
并延长交
于点M.
(1)试猜想
与
的位置关系和数量关系,并说明理由.
(2)若
,
,求
的长.
(3)如图 2,在线段
的延长线上各取一点F,E,使得
,连接
并延长交
于点M.
请问:(1)中的结论还成立吗?如果成立,请给出证明;如果不成立,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e2d3ea3bdfca7111b823bb1c381a0f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef5168335544ab74e8107b46ab5b7ec6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7c4491b334748bceb87485a33b38638.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/15/d8698719-cf61-45de-9e10-08a9b2f7a087.png?resizew=373)
(1)试猜想
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080ca48cd27d4bf9d9ef084b558fc17a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2fc28f622892dd18bbbac95d541acfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
(3)如图 2,在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b471b67fdc27dff654cd8f0fa909fbfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7c4491b334748bceb87485a33b38638.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccaee8f228ff24e7c89879bb5b999cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
请问:(1)中的结论还成立吗?如果成立,请给出证明;如果不成立,说明理由.
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解答题-问答题
|
较难
(0.4)
【推荐2】在矩形
中,
,
,
于M,
分别交
,
于点E,F,
分别交
,
于点G,H.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/27/b5b08e44-2bb8-4fad-aca8-7c3a3e116ad6.png?resizew=448)
(1)【观察猜想】如图①,当
时,线段
与线段
的数量关系是 ;
(2)【类比探究】如图②,当
时,(1)中的结论是否仍然成立?若成立,请说明理由,若不成立,请写出正确的结论,并说明理由;
(3)【拓展运用】如图③,在四边形
中,
,
,
于G,点E、F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/6d42e97eee705d164e6ac6de9ecd6d1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c52b857c7ca55dfa6da108df1d3cee2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de64cbea23ec8a57a4705d9f16297d80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/27/b5b08e44-2bb8-4fad-aca8-7c3a3e116ad6.png?resizew=448)
(1)【观察猜想】如图①,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f22fec5a381ae8aca93d876e54c79de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
(2)【类比探究】如图②,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2958030ec9d7543dda1f529593a915e2.png)
(3)【拓展运用】如图③,在四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b2bd91f349635360176cb740568d257.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21eb847a1722ed6e10e23c59d53fe7d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61fe81d0b136fc2acc97ab50ffbf6edf.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/a2d371e4ae1191dfe763bf14df935a3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐1】点P为等边三角形
所在平面内一点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/9/67564bb0-f832-4cc4-a7ef-2f4f9b2541a1.png?resizew=416)
(1)如图1,点P在
外部,若
,
,则
的长为______;
(2)P点在
内部,连接
.
①如图2,若
,求证
;
②如图3,D为
边中点,连接
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5b47e792146e2f7d93a9ef9ad1294ed.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/9/67564bb0-f832-4cc4-a7ef-2f4f9b2541a1.png?resizew=416)
(1)如图1,点P在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f83f70e69dca65099b91f61878b1ca27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4700db4caa77fdcfa7a2e19bc7dc5781.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
(2)P点在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
①如图2,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d462ecbfd4c6937d4a58725b809df966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46471be5c5e2db5a34abfcdf5df30f2c.png)
②如图3,D为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af72f1d8e11fe07e8bc26bca8be91ca6.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐2】已知:在矩形
中,
,
,点G是边
的中点,连接
.以点A为圆心、2为半径作
,点E是
上的一个动点,连接
、
.将线段
绕点E逆时针旋转
得到线段
,连接
、
、
.
(1)如图1,当点E在直线
的左侧时,试证明
,并求出
的长;
初步探索
(2)直接写出
的最小值是 ,最大值是 ;
操作并思考
(3)如图2,当点E落在边
上时,试猜想
和
有怎样的位置关系,并说明理由;
(4)若点E到G、F之间的距离相等,请根据图1、图3两种情况,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04ee826937d2add7a93aaa1422f8b736.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06e322e0c87479bba874db9ae9ba36b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c20d0b44025a639ce3a92d639dae587.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c20d0b44025a639ce3a92d639dae587.png)
![](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/ccaee8f228ff24e7c89879bb5b999cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e57a13c665af88f326c9890072bf73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
(1)如图1,当点E在直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5ddc939bfcba0a8c2ffeada4315e03f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e57a13c665af88f326c9890072bf73.png)
初步探索
(2)直接写出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
操作并思考
(3)如图2,当点E落在边
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06e322e0c87479bba874db9ae9ba36b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
(4)若点E到G、F之间的距离相等,请根据图1、图3两种情况,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
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