如图1,在
中,
,
,点
、
分别在边
、
上,
,连接
.将
绕点
顺时针方向旋转,记旋转角为
.
(1)[问题发现]
①当
时,
______;
②当
时,
的值是多少?请给出证明过程.
(2)[拓展研究]
试判断:当
时,
的大小有无变化?请仅就图2的情形给出证明;
(3)[问题解决]
在旋转过程中,
的最大值是多少?请直接写出答案.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e3262fc038bbec5e7c8cc47df08bef7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/630d82ae0ed6deb825514e0bc92e74a0.png)
![](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/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62ceb3cc7e4c368c7b13a65d463f3c60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/12/361973e9-54ef-4d87-982f-b05466adc897.png?resizew=421)
(1)[问题发现]
①当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/469451242301adbf795110cbb9154403.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc00342101809b43c1c3187dc0d06f9b.png)
②当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31cb3cc93e355ace2adee68be0a068f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1672bf7cfa9a741651889f41855f6f3b.png)
(2)[拓展研究]
试判断:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef047d4e8392c80f84689e659a7a98e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1672bf7cfa9a741651889f41855f6f3b.png)
(3)[问题解决]
在旋转过程中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
更新时间:2023-12-09 15:13:15
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】正方形
的边长为5,E、F分别是
边上的点,且
,将
绕点D逆时针旋转
,得到
.
;
(2)若
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/374fe9986ebbc986fc422e514ab93a51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/345c91c9e67e6ee00a872078ab17f094.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63b43490ca09467a4c8cd8cfe91c94e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/366f51d41a3989f78882fb1358fa6119.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c5e1406b4f4ee0a28602a44f6f3eaeb.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30b0393ce62b24aa5f9b740d4cc6743b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】【阅读材料】两个顶角相等的等腰三角形,若它们的顶角具有公共的顶点,且当把它们底角的顶点连接起来时会形成一组全等三角形,则把具有这种规律的图形称为“手拉手”图形,如图1,在“手拉手”图形中,若
,
,
,则
≌
.
(1)【材料理解】在图1中证明.
(2)【问题解决】如图2,
和
都是等腰三角形,
,
,
,线段
与线段
交于点F,延长
交
于点
,求证:
.下面是小明的部分证明过程:
证明:∵
,
,
∴
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e37f37f6a0cf3f9b7ee43ad199cdb98.png)
∵
,
∴
.
请你补全余下的证明过程.
(3)【结论应用】如图3,
是等腰三角形,
,
、
分别为边
、
上的点,且满足
,连接
,将
以点
为旋转中心按逆时针方向旋转,旋转角为
,当线段
与
的腰有交点,且直线
垂直于
的腰时,直接写出
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8abfdaab699cfe51bb9678110ad6aee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcb49df05f2e31d005735c3f14a21d30.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/22/21e3378e-b3f0-47d9-9534-cf8c5d4edbb6.jpg?resizew=495)
(1)【材料理解】在图1中证明.
(2)【问题解决】如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8abfdaab699cfe51bb9678110ad6aee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21037e170bdbb322558e79c40c00b454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e9395bbd17b9c334dcd6d52e0607740.png)
证明:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39b37f206e1cc362a8ca1da596f613a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e37f37f6a0cf3f9b7ee43ad199cdb98.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8abfdaab699cfe51bb9678110ad6aee.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ecf0b437f9a3b91a02abd523c04e1e4.png)
请你补全余下的证明过程.
(3)【结论应用】如图3,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8b3ccbed8aa44da96fbf16bb9978b48.png)
![](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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c54ce139ae5d63691cac8a1ce5bbfe4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,在矩形
中,
,
,点P从点A出发,沿
以铅秒1个单位长度的速度向终点C运动,点Q从点C出发,沿
以每秒2个单位长度的速度向终点A运动;当点P停止运动时,点Q也随之停止,点P、Q同时出发,设点P的运动时间为t(秒).
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/16/dc4bfa5d-a8aa-4d15-9778-2f88babd7209.png?resizew=144)
(1)
的长是_________;
(2)用含t的代数式表示
的长;
(3)设点Q到
的距离为y,求y与t之间的函数关系式;
(4)若点C关于直线
的对称点为
,当
时,请直接写出直线
与
的直角边
平行或垂直时t的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c593ebdb2f1934a0cb56f8c44f454f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4494a85de0be0b97a69348115aef8513.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07160f14b3b453bebb64cb2bf96dc85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afc0d8c4e945e4230252a7b4c97d39ad.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/16/dc4bfa5d-a8aa-4d15-9778-2f88babd7209.png?resizew=144)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(2)用含t的代数式表示
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
(3)设点Q到
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9abaeba15f3abdd877bc701af52c5cd9.png)
(4)若点C关于直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4c8a9c4957431681ddfc77895a88508.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c052fc4d2a1d08dc58e6264f32a859f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7096fdcee49451970e84214dee5c2e5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】在△ABC中,AD是△ABC的高,矩形EFGH的顶点E、H分别在边AB、AC上,FG在边BC上,且两邻边之比EF:FG=5:9,若AD=16cm,BC=48cm,求矩形EFGH的面积.
![](https://img.xkw.com/dksih/QBM/2015/11/19/1573930239770624/1573930246299648/STEM/8155e15923d44e37b597d3ef644fd268.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图,已知AD是△ABC的角平分线,⊙O经过A、B、D三点,过点B作BE∥AD,交⊙O于点E,连接ED.
(1)求证:ED∥AC;
(2)连接AE,试证明:AB•CD=AE•AC.
(1)求证:ED∥AC;
(2)连接AE,试证明:AB•CD=AE•AC.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/23/3211c6fd-86dc-4c3d-aa66-54a6061cb913.png?resizew=218)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】如图,点
是
的边
上一点,以点
为圆心,
为半径作
,与
相切于点
,连接
,
,
交
于点
,连接
并延长交
的延长线于点
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/1/fdb77bca-aa10-49d9-9bff-62bd54dd5ca5.png?resizew=173)
(1)求证:
是
的切线;
(2)若
,
,求
的半径.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a299d2b999568e80be8005565ba209a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f15e0ab4e0d3e405fb82c50afb882f2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/1/fdb77bca-aa10-49d9-9bff-62bd54dd5ca5.png?resizew=173)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ebb33adb2310a6e03918761e68204a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4494a85de0be0b97a69348115aef8513.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
您最近一年使用:0次