如图,
,
,
,求证:
且
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b8bee1c892473f71a723860b933e234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8ce1475f537b4ad21775bfaa16daa0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92034dd2bb9480b18709d01153467f8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/550b15375a54ce849585b60bc42d2dd1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/12/abcb9ce6-eb88-4f80-a1c9-27e1b4204f61.png?resizew=157)
更新时间:2023-02-11 15:26:36
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】如图,在三角形
中,D,E是
上的点,F是
上一点,H,G是
上的点,
于点D,连接
,
,
.给定三个条件:①
,②
,③
.
(2)证明上述命题.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c33daacca5f6f6681b662295ebb98587.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589786dd7c3a2679c3230b671cd232d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e55e398e8520d8a36fb5a625a085b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb023313112cd8a6068d013fdcc9a193.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23fef5befef0868732e211b867287919.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4069abed7185fd1382f58125786cb952.png)
(2)证明上述命题.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】已知
,点
为平面内的一点,
.
![](https://img.xkw.com/dksih/QBM/2022/1/25/2902291254509568/2902862225170432/STEM/bbdeae6dadab49979559f4df5d87263e.png?resizew=456)
(1)当点
在如图①的位置时,求
与
的数量关系.
解: .(根据如图填射线
的画法)
因为
,
所以
( ).
所以
(两直线平行,内错角相等);
(请继续完成接下去的说理过程)
(2)当点
在如图②的位置时,
与
的数量关系是 (直接写出答案);
(3)在(2)的条件下,如图③,过点
作
,垂足为点
,
与
的平分线分别交射线
于点
、
,回答下列问题(直接写出答案):图中与
相等的角是 ,
度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0487441cafe2b5263cfbce41c6a8fa38.png)
![](https://img.xkw.com/dksih/QBM/2022/1/25/2902291254509568/2902862225170432/STEM/bbdeae6dadab49979559f4df5d87263e.png?resizew=456)
(1)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df92344b00e2aa8e7f0d1fa997b9dd04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c543c3ddc3723fde6bbfca3ea3b921b.png)
解: .(根据如图填射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdb0536d40d1f37d74032fcb66f29463.png)
(请继续完成接下去的说理过程)
(2)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df92344b00e2aa8e7f0d1fa997b9dd04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c543c3ddc3723fde6bbfca3ea3b921b.png)
(3)在(2)的条件下,如图③,过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9301ad0164a3b7cadacb775435a811c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db095c4dd1b97bcb22c417482b829888.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33baaa05c04f6b132fc97dd0930cf44c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccaee8f228ff24e7c89879bb5b999cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df92344b00e2aa8e7f0d1fa997b9dd04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8bd8908eae9e3ef724c064e807eb954.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】已知
,以三边为斜边向外作等腰直角三角形
.
为等边三角形时,
①填空:
;
②证明:
.
(2)如图2,当
为直角三角形,
时,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/866a014907c13d2dac6f4023add5e86c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
①填空:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32e910dce5a57ff0d917e0b4dd620214.png)
②证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ff56ea00ca90825f3d95809de24f639.png)
(2)如图2,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ff56ea00ca90825f3d95809de24f639.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】已知:如图,BE是⊙O的直径,BC切⊙O于H,弦ED∥OC,连接CD,并延长交BE的延长线于点A.,
![](https://img.xkw.com/dksih/QBM/2022/3/24/2943186345238528/2963929735249920/STEM/ebea9c5a-fe1b-46ec-9fa8-51171c09a0d0.png?resizew=187)
(1)证明:CD是⊙O的切线;
(2)求证:DE·OC=
BE2.
![](https://img.xkw.com/dksih/QBM/2022/3/24/2943186345238528/2963929735249920/STEM/ebea9c5a-fe1b-46ec-9fa8-51171c09a0d0.png?resizew=187)
(1)证明:CD是⊙O的切线;
(2)求证:DE·OC=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
您最近一年使用:0次