已知:如图,点
在
边上(不与点
,点
重合),
在
边上(不与点
,点
重合),连接
,
,
与
相交于点
,
,
.
有以下四个结论:
①
;
②
;
③
;
④
.
(2)请从(1)中任选一个结论进行证明.
![](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/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.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/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.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/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/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4354365ca0929f8a606ed0bf341e4ca.png)
有以下四个结论:
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/024dc2ccbbe321774df5d44e8785b203.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea76d20f1b5236411cda78c91e55ec5d.png)
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38cd91b7c5ead4d850879e9422273600.png)
④
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c640341ee983acb176ea5cc2a986b41.png)
(2)请从(1)中任选一个结论进行证明.
更新时间:2024-05-20 20:38:32
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】如图1,已知∠DAF=∠B=90°,DF
CE,AD=BC,AB=CD.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/23/dfe827e6-fa01-4a39-b76c-154e3a77f30a.png?resizew=374)
(1)求证:EF=CD;
(2)如图2,延长FD到M,连接CM,若△CDM与△CEB关于CF对称,∠BEC=50°,求∠DFC.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/23/dfe827e6-fa01-4a39-b76c-154e3a77f30a.png?resizew=374)
(1)求证:EF=CD;
(2)如图2,延长FD到M,连接CM,若△CDM与△CEB关于CF对称,∠BEC=50°,求∠DFC.
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解答题-作图题
|
适中
(0.65)
【推荐2】综合与实践
综合与实践课上,老师让同学们以“角的变化与全等三角形”为主题开展数学探究活动.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/19/4d03a61b-5485-4d19-a93b-9fc23ba20c24.png?resizew=352)
(1)操作判断
如图1,已知
.
操作一:以直角顶点
为圆心,适当长为半径画弧,与
的两边分别交于点
,
.
操作二:在
的内部任意画射线
,过点
作
于点
,过点
作
于点
.请用直尺和三角板按操作二将图1补充完整,并直接写出
与
的数量关系:________.
(2)类比探究
将
由直角换成锐角,继续探究,过程如下:
按(1)中操作一的方式操作,如图2,点
,
分别在
的边
,
上,点
,
都在
内部的射线
上,
,
分别是
,
的外角,且满足
.请判断(1)中的结论还成立吗?请说明理由;
(3)拓展应用
最后,老师根据课堂探究的内容编制了一道数学题,请你解答.
如图3,在
中,
,
,点
在
边上,
,点
,
在线段
上,
,若
的面积为
,请直接写出
和
面积的和.
综合与实践课上,老师让同学们以“角的变化与全等三角形”为主题开展数学探究活动.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/19/4d03a61b-5485-4d19-a93b-9fc23ba20c24.png?resizew=352)
(1)操作判断
如图1,已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39cb59543ccf42b37ebce3f67416e561.png)
操作一:以直角顶点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/358c69b4f6c350c35d19d33c69f2a2a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
操作二:在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/358c69b4f6c350c35d19d33c69f2a2a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c897a54f2e36bc4b52fba74b41c89d2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b62ce0cbffa4758c7a0e6fb7ca4d24e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
(2)类比探究
将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/358c69b4f6c350c35d19d33c69f2a2a8.png)
按(1)中操作一的方式操作,如图2,点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/358c69b4f6c350c35d19d33c69f2a2a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.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/358c69b4f6c350c35d19d33c69f2a2a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5b69d40b75d582c4b8ffa2369af1d41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d57899ad4774aed9ccc7bd23db72153.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e742966e3711cfa53dce04022acf4bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8de92314656534d33816fb721b708e0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f30c7c88c25476db5741b5c5bfc22df5.png)
(3)拓展应用
最后,老师根据课堂探究的内容编制了一道数学题,请你解答.
如图3,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2da1d50433aecf541991fd0f01773cb.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/f8cabcef1cee1213140371c499339864.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/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/feb8772571a04e4eb48f7772592d18a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b184c94e38f1e5dbe750b2168c2a37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e742966e3711cfa53dce04022acf4bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5df7626240940eb340420a605e95aeee.png)
您最近一年使用:0次