名校
1 . 如图是大众汽车的标志图案,其中蕴含这一些几何知识,根据下面的条件完成证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a755edadca4e4fc27fd49559b8d691ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d1ee1dd2054a26bdbe4d8821ecfa1d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54b4908b37cf23de34d38ae7a0bff278.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f3c184f27f44cf12345d4e0ba9d352b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3818a2c9919d358b4c3713396093822b.png)
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2024-03-21更新
|
290次组卷
|
3卷引用:山东省青岛市2023-2024学年七年级下学期 单元测试题
2 . 补充完成下面的推理过程.
如图,已知点
分别是
的边
上的点,
,
.求证:
.
,( 已知 )
( )
,
( )
( )
如图,已知点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/927456b0989846a2f1573844bbaa2105.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bee14312eec42c729aab9880e09d3726.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c0aa4c793921fdaa5d430cb90d78ca6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5b3f839ce88bf970aceb44ab939bd5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8124688c0c1330a37afac0d6996c45e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/093d5f28c9dc6bdc0c6620ab8ce9bea8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d70da26f3b2239b6e13b704c31ac7884.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8432fa69f5b8a830b8f199e11e580862.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c73c256acb5e374fef82ea9653322821.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c73c256acb5e374fef82ea9653322821.png)
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名校
3 . 填空,完成以下解题过程:
如图,已知
,直线
分别交
,
于点E,F,
,求证:
.![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16f3d198e76391779fa3badc848c8ac8.png)
,(已知)
________(_____________________________________)
又![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c08980b6afedc04aa04f385791f0163.png)
( )
即
________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
________.(__________________________________)
如图,已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.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/0e53497af8899cb299d762f1a4f46a55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b74be26b6f8943e3d639a3dc3dce552.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16f3d198e76391779fa3badc848c8ac8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ed863037d0485ba14aa5a425f4dc1a2.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c08980b6afedc04aa04f385791f0163.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f023eb4394116a6fbb479bac223c00f6.png)
即
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f209457946ad32b0a576498dcecf5c02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7a407b262c22419f73396170ecdc849.png)
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2024-03-27更新
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432次组卷
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2卷引用:广东省广州市番禺区广东仲元中学2022-2023学年七年级下学期期中数学试题
4 . 阅读理解,补全证明过程及推理依据.
已知:如图,点
分别在
上,
于点
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f24a813ce182e99b7f9a6d6e2894d61.png)
.
证明:
(已知)
(______)
又
(______)
______(______)
(______)
(______)
又
______
(平角的定义)
______![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83873a9d782f2588c5eedbfe73f9bc2f.png)
又
(已知)
(______)
______(内错角相等,两直线平行)
已知:如图,点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cf9b288c48c73463a2f214f02b6952a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c28d2790a97390935125aa897417f970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78a598a35e6a4bfb3a5f08b55b70bdc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04ea5d581e0305727d96bcaf3a1d4048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f24a813ce182e99b7f9a6d6e2894d61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/163e2eb13b42eb3d675ba133b96fff40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3ff4e460f9a8e58a42f840c9d36b447.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18c3f08d60099e4e7c207774f64304fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5ce969cf5583ec1467ecf0c47b85f77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd91eb5e79836515f6d09c524bea4139.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f97fbf2cd96de44489256fb56ab11a61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83873a9d782f2588c5eedbfe73f9bc2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a0b413bfd00f3e2b67a6e4709287934.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83873a9d782f2588c5eedbfe73f9bc2f.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9de23caef9b95777756f750600533b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69e028a9c89411a461aef2f84f541609.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
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5 . 探究三角形的内角和
(1)下面是证明三角形内角和定理的一种添加辅助线的方法,请完成证明.
三角形的内角和定理:三角形的内角和等于
.
已知:如图,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89567a6d65ab9ac80fef298f6f76592b.png)
证明:在
上任取一点
,过点
作![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a6c6e7c025362c46a64a8956761f08e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
,交
于点
,过点
作![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a679040c4d556723e482bacbab41356d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
,交
于点
.
(2)请再用一种不同的方法证明三角形内角和定理.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/24/04e5499d-3d2e-45dc-af6b-9e85a630468b.png?resizew=190)
(1)下面是证明三角形内角和定理的一种添加辅助线的方法,请完成证明.
三角形的内角和定理:三角形的内角和等于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95e1dcdc9d50fe147e3924ce30bba519.png)
已知:如图,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89567a6d65ab9ac80fef298f6f76592b.png)
证明:在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a6c6e7c025362c46a64a8956761f08e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a679040c4d556723e482bacbab41356d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1a9c6a736e6eac98a676fa3232db5a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
(2)请再用一种不同的方法证明三角形内角和定理.
您最近一年使用:0次
2023-11-20更新
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213次组卷
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4卷引用:山西省吕梁市交城县2023-2024学年八年级上学期期中数学试题
山西省吕梁市交城县2023-2024学年八年级上学期期中数学试题(已下线)专题01 三角形(12大考点+过关检测)-【寒假自学课】2024年八年级数学寒假提升学与练(人教版)(已下线)专题7.12 认识三角形(知识梳理与考点分类讲解)-2023-2024学年七年级数学下册基础知识专项突破讲与练(苏科版)(已下线)专题7.23 平面图形的认识(二)(全章知识梳理与考点分类讲解)-2023-2024学年七年级数学下册基础知识专项突破讲与练(苏科版)
6 . 阅读下列材料,回答问题.
我们在小学就已经知道,任意一个三角形的内角和等于
.
我们是通过度量或剪拼得出这一结论的.但是,这种“验证”不是“数学证明”;所以,需要通过推理的方法去证明:任意一个三角形的内角和一定等于
.
探究:在纸上任意画一个三角形,将它的内角剪下拼合在一起,就得到一个平角.如下图两种方法.
.证明过程如下:
已知:如图,
.
求证:
.
证明:如图,过点
作![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c436f108fd4921dae15ecff19270237e.png)
∵![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c436f108fd4921dae15ecff19270237e.png)
∴
(______________________)
同理![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51efb5f518d67bdd7b1d782917f7e1ec.png)
∵
(________________)
∴
(________________)
(2)由图2启发,可以得到证明三角形的内角和等于
的另一种证法,请你完成.
我们在小学就已经知道,任意一个三角形的内角和等于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfe639eab78eafd2d40ea70aa5d3f21d.png)
我们是通过度量或剪拼得出这一结论的.但是,这种“验证”不是“数学证明”;所以,需要通过推理的方法去证明:任意一个三角形的内角和一定等于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfe639eab78eafd2d40ea70aa5d3f21d.png)
探究:在纸上任意画一个三角形,将它的内角剪下拼合在一起,就得到一个平角.如下图两种方法.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfe639eab78eafd2d40ea70aa5d3f21d.png)
已知:如图,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/791e819abbe4ecc6f2e7209839c4fc0b.png)
证明:如图,过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c436f108fd4921dae15ecff19270237e.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c436f108fd4921dae15ecff19270237e.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a019cec6cab7b8013889f17fa1bd15e.png)
同理
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51efb5f518d67bdd7b1d782917f7e1ec.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da98162687d4625d1364bd6cbf11fe82.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c8ee8e3a10ea554320bf3fd3263185d.png)
(2)由图2启发,可以得到证明三角形的内角和等于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97d6cf1e736299e674157aa3ee48d522.png)
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7 . 学习了等腰三角形知识后,小明进行了研究,他发现当三角形的一条外角平分线平行于三角形的一条边时,该三角形为等腰三角形.请根据他的思路完成以下作图与填空:用直尺和圆规,作
的角平分线
(只保留作图痕迹).
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/17/bc1da0bc-6e15-4aa8-a5c5-f7fd63e09c1c.png?resizew=145)
已知:如图,
为
的一个外角,
平分
,且
.
求证:
为等腰三角形.
证明:∵
平分
,
∴
① .
∵
,
∴
② , ③ =
,
∴
④ ,
∴
⑤ ,
∴
为等腰三角形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/721c75fcd58d3d54260aad0f82e09e37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/17/bc1da0bc-6e15-4aa8-a5c5-f7fd63e09c1c.png?resizew=145)
已知:如图,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/721c75fcd58d3d54260aad0f82e09e37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/721c75fcd58d3d54260aad0f82e09e37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e932b4add3175358f15be0e1f7104e79.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
证明:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/721c75fcd58d3d54260aad0f82e09e37.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32e910dce5a57ff0d917e0b4dd620214.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/542b5bc10c7341c04c22244f3ec16e6a.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32e910dce5a57ff0d917e0b4dd620214.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/194741f4d2ae7ee44cafca780361446a.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afde09d82ae96f00c135732baee64776.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c26a46e7879436d532af3f4b6e258a81.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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8 . 如图,已知
.求证:
平分
.
( ),
__________(__________),
__________(__________).
(已知),
__________=__________(等量代换).
平分
(__________).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/791bbe0f37d1cc23a50e4cd7f398323d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdb8eca20ce2c918ea4034ea15210c7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/699eef585d3c18c36669ce7e8c50af9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afde09d82ae96f00c135732baee64776.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2a8bf5e05a07c93a7104839fc21849.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc12bd8bfc5a8ae8660a941e58028925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95957ded3d7aae8a854a65ce2f00e04a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdb8eca20ce2c918ea4034ea15210c7f.png)
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名校
9 . 推理填空:
如图,已知
,
.点E为射线
上一点,点F为线段
上一点,连接
,
求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1fcdb81941530edee13b29936141a34.png)
∵![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a8ea7df6fb067a4ad237f77856a25c9.png)
∴
( )
∵![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dceb5cc71fc50f20649f6b9535fd914.png)
∴
( )
∵
( )
∴ ( )
∴
( )
∵![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a8ea7df6fb067a4ad237f77856a25c9.png)
∴
( )
∴
∴
如图,已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dceb5cc71fc50f20649f6b9535fd914.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1393308bc68322f50fa29702dd412263.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1fcdb81941530edee13b29936141a34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12850119b4a552fd2f31178210ba7f9f.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a8ea7df6fb067a4ad237f77856a25c9.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b83764876be47a196fd5f408763738a.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dceb5cc71fc50f20649f6b9535fd914.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/459459559720ab5e154a80723c47cc30.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1393308bc68322f50fa29702dd412263.png)
∴ ( )
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76644ca2e1256967f218b1f40c358ed3.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a8ea7df6fb067a4ad237f77856a25c9.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5172614b79a5fa6df868a1a70baeba1d.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2a8bf5e05a07c93a7104839fc21849.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1fcdb81941530edee13b29936141a34.png)
您最近一年使用:0次
10 . 完成下面的证明.
如图,点
、
、
分别是三角形
的边
、
、
上的点,
,
.求证:
.
,
∴
( ),
∵
,
∴
( ),
∴
.
如图,点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.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/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9abaeba15f3abdd877bc701af52c5cd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/696644c4fb1a1dd5d8ea2cbb2d15b1a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f245bb8ddbac5c607b47f81cc9848576.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8124688c0c1330a37afac0d6996c45e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/696644c4fb1a1dd5d8ea2cbb2d15b1a8.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2a8bf5e05a07c93a7104839fc21849.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f245bb8ddbac5c607b47f81cc9848576.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb651ac2cf8469d28f85e608dc047d14.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8124688c0c1330a37afac0d6996c45e.png)
您最近一年使用:0次