1 . 阅读与思考
阅读下面材料,并按要求完成相应的任务
下面是创新学习小组利用折叠正方形纸片来探究折叠中的锐角三角函数问题:
如图,正方形
边长
,点E是
边上的一个动点,沿着
折叠
,点B落在点F处.求
的值.
【特例探究】
任务一:
(1)如图1,创新学习小组发现在点E运动过程中,当点F恰好落在正方形的对角线
上时,则
______.
任务二:
(2)如图2,当点E运动到边
的中点时,点B落在点F处,求
的值.
下面是该结论的部分解答过程:
在图2中,过点F作
于M,延长
交
于N.
易证四边形
为矩形,______
,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aef4362d34fbff6a60d6cbbd54abbc48.png)
∴设
,则
,
,
,
在
中,根据勾股定理得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/470d45962fbeebae4e332cd0d18698f8.png)
解得:
(舍去),![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8287a28f14ba2fb150a4f3a418e85a0.png)
即![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69743bc3e98fbf8a91d35f6b51e8509a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef2d556d54ef14a99ff2e0f793287d6d.png)
∴在
中,
______
仔细阅读上面的证明过程,按照上面的证明思路,请你将横线部分补充完整.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/26/af85e3ab-9b65-4143-b4c7-f70b506c38d8.png?resizew=484)
【方法应用】
任务三:
(3)如图3,当点E运动到边
靠近点C的三等分点时(即
),点B落在点F处,请你类比(2)中的方法求
的值.
阅读下面材料,并按要求完成相应的任务
正方形的折叠 正方形是日常生活中常见的一种基本几何图形,具有特殊平行四边形的一切性质,因此,平时做题时经常会遇到正方形的折叠问题,虽然折叠的形式多样,给同学们带来各种困惑,但我们只要把握它的两大特点:①折叠前后折痕两侧图形全等;②折叠前后对应点的连线被折痕所在的直线垂直平分;并且掌握解决折叠问题的两大方法:①利用勾股定理构建方程;②巧用“一线三直角”构建相似三角形解决问题,这类问题一般都能解决. |
如图,正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/305a88d4e0249bd16d48eda01331d2d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e742966e3711cfa53dce04022acf4bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c978b9bb74bc1194e5d1313cd7615d4d.png)
【特例探究】
任务一:
(1)如图1,创新学习小组发现在点E运动过程中,当点F恰好落在正方形的对角线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd39c7426cb105eb1df6021e28c5b319.png)
任务二:
(2)如图2,当点E运动到边
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c978b9bb74bc1194e5d1313cd7615d4d.png)
下面是该结论的部分解答过程:
在图2中,过点F作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da5af132cde2fa211adebf4ef6e2d6fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907d5147cea4c9ce855074864fe54506.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
易证四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a02b1139e07e431b5d4276757b232bad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb33f31195f730a4f73202a0773daafa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aef4362d34fbff6a60d6cbbd54abbc48.png)
∴设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50709b7f239faeff223ee71f73991b39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c94f537af268ea03e9db42c8f7096a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9902ed4acc79b4aa899f0c058010c36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31429b136a455a265af0a93cbd628789.png)
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a4630ffb41acd70aa20f946502f4957.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/470d45962fbeebae4e332cd0d18698f8.png)
解得:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62b6ab454199d2738ea1b5cefb133d50.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8287a28f14ba2fb150a4f3a418e85a0.png)
即
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69743bc3e98fbf8a91d35f6b51e8509a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef2d556d54ef14a99ff2e0f793287d6d.png)
∴在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a4630ffb41acd70aa20f946502f4957.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c268d3b5c4bc955e51a1f49e613017b.png)
仔细阅读上面的证明过程,按照上面的证明思路,请你将横线部分补充完整.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/26/af85e3ab-9b65-4143-b4c7-f70b506c38d8.png?resizew=484)
图1图2图3
【方法应用】
任务三:
(3)如图3,当点E运动到边
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e73c8c1d2ba6b29b301380a45dfbcdd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c978b9bb74bc1194e5d1313cd7615d4d.png)
您最近一年使用:0次
2 . 请阅读材料,并完成相应的任务.
战国时期数学家墨子提写的《墨经》一书中就有了圆的记载,与圆有关的定理有很多,弦切角定理就是其中之一.
定义:我们把顶点在圆上,一边和圆相交,另一边和圆相切的角叫做弦切角.(也就是切线与弦所夹的角,切点为弦切角的顶点).如图1中
即为弦切角.
弦切角定理:弦切角的度数等于它所夹的弧所对的圆周角度数.
下面是弦切角定理的证明过程:
①如图1.已知:
为圆上任意一点,当弦
经过圆心
,且
切
于点
时.
易证:弦切角
.
②如图2.当点
是优弧
上任意一点,
切
于点
.
求证:弦切角
.
证明:连接
并延长交
于点
,连接
,如图2所示.
与
相切于点
,
______,
,
是直径,
(_____),
,
,
又
(_______),
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/25/7330e30c-b196-4bd3-9395-9e8d082d209a.png?resizew=461)
完成下列任务:
(1)将上述证明过程及依据补充完整;
(2)运用材料中的弦切角定理解决下列问题:
①如图3,
的顶点
在
上,
和
相交于点
,且
是
的切线,切点为
,连接
.若
,
,求
的长.
②如图4,
,
,以
为直径的
交
于点
,过点
作
的切线,交
的延长线于点
.直接写出
与
的数量关系:______.
战国时期数学家墨子提写的《墨经》一书中就有了圆的记载,与圆有关的定理有很多,弦切角定理就是其中之一.
定义:我们把顶点在圆上,一边和圆相交,另一边和圆相切的角叫做弦切角.(也就是切线与弦所夹的角,切点为弦切角的顶点).如图1中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76bc8e50eeccced1d7f3bc52e09a7d03.png)
弦切角定理:弦切角的度数等于它所夹的弧所对的圆周角度数.
下面是弦切角定理的证明过程:
①如图1.已知:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d97dc3b752832906de41447bb58a341.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
易证:弦切角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1a5c65024d2f53dde6078f63802c851.png)
②如图2.当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d97dc3b752832906de41447bb58a341.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
求证:弦切角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/940699bc6596266f000d99efff2954d4.png)
证明:连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12d8da10b2137a1e87801556a313e625.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/167d31eb8432b5c0364316e5048c23dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf6dc86d2e23673cf1acec2621cb11b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d4eb4f399b198988b2a0e7434f54161.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4feb815daac8f4eac9e95c60e0d4f915.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7029f81e24713dc9413b72f65e788fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b43db7f6fbc54ca56c7377b9c2afebd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12b81d3d6762b3e559de699c4b943301.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef5ed240bfc4eb6bbaf388e1dfd3e140.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20e5e96b796b2570a5cfddaece73c981.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1fd128f2cf911ad635ee3d8b58c1ed3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/25/7330e30c-b196-4bd3-9395-9e8d082d209a.png?resizew=461)
完成下列任务:
(1)将上述证明过程及依据补充完整;
(2)运用材料中的弦切角定理解决下列问题:
①如图3,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](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/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eca7e1a727ba332984ad857b3d25344d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
②如图4,
![](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/f52a58fbaf4fea03567e88a9f0f6e37e.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/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76bc8e50eeccced1d7f3bc52e09a7d03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
您最近一年使用:0次
3 . 如图,在矩形
中,
,
,作对角线
的垂直平分线
,垂足为G,交
于点F,过点G作
,垂足为H,则
的值为( )
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/24/077b1cfe-6e68-41e0-95c9-d2c1e003e7b7.png?resizew=182)
![](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/07140f277a35733d8c97577ccdd4e3ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09b676dfde981c8baab99e65a6e1966c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/311ff23e560135923e2eed0bab3b15ea.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/24/077b1cfe-6e68-41e0-95c9-d2c1e003e7b7.png?resizew=182)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
4 . 如图,在
中,
是对角线,
是边
上的靠近点
的三等分点,连接
交
于点
,则
的值为( )
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/21/e16e6b79-3408-4d9d-9984-d373ef3649ca.png?resizew=174)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5138a9f70d5e8b0580e30fef6eb7baef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/126e9cb9dd29d15c3d3d1e4ea2071538.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/21/e16e6b79-3408-4d9d-9984-d373ef3649ca.png?resizew=174)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
5 . 阅读与思考
下面是一位同学的数学学习笔记,请仔细阅读并完成相应任务.
任务:
(1)填空:材料中的依据是______;
(2)如图,在梯形
中,
,点E在
上,
交
于点F,若
,
,
,求
的长.
下面是一位同学的数学学习笔记,请仔细阅读并完成相应任务.
我们知道连接三角形两边中点的线段叫做三角形的中位线.通过证明可以得到“三角形的中位线平行于三角形的第三边,且等于第三边的一半”,类似三角形中位线,我们把连接梯形两腰中点的线段叫做梯形的中位线. 如图,在梯形 ![]() ![]() ![]() ![]() 求证: ![]() ![]() 证明:∵ ![]() ∴ ![]() ∵F为DC的中点, ∴ ![]() 在 ![]() ![]() ![]() ∴ ![]() ∴ ![]() ![]() ∵E是AB的中点,F是AG的中点, ∴EF是 ![]() ∴ ![]() ∵ ![]() ∴ ![]() |
(1)填空:材料中的依据是______;
(2)如图,在梯形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee73452ee4d5437f1399f1235b95e55f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/611c69d5fed776d58bc949a5323d6a04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0d5a2cd05e4476fc72271e8fdb59a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7788830ed1cb3b9c5988f70f43595f2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/12/a2a97121-fe4f-4329-baff-61e3997ab1e7.png?resizew=105)
您最近一年使用:0次
6 . 如图,在矩形
中,对角线
相交于点O,
的平分线分别交
于点F,E.若
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f79997547fb75e88ad1e2c66989a4a0.png)
______ .
![](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/2947ca8e0cdbeb4aab80ce9e7b63ba98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9d7063a599e75a0caff1019fcf9eb85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f656e1d1f68954e5f06de8958f6a9310.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f79997547fb75e88ad1e2c66989a4a0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/12/f9341f72-a79e-4b70-afb8-e5caa8e6a84b.png?resizew=182)
您最近一年使用:0次
7 . 综合与实践
问题情境:
在“综合与实践”课上,老师提出如下问题:如图1,
是线段
上的一点,以
和
为直角边分别作等腰直角
和等腰直角
,点
在边
边上,连接
和
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/10/729d8307-29e4-4e6e-bc21-8b2ea6d9636e.png?resizew=150)
独立思考:
(1)试判断
和
的位置关系,并说明理由.
实践探究:
(2)“聪慧小组”受此问题的启发,将图
中的
绕着点
逆时针旋转角度
,使得点
落在
的外部,得到
,点
的对应点为
,点
的对应点为
,连接
,
,如图
,请判断
与
之间的位置关系,并加以证明.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/10/b7081816-6ee7-4fae-b917-e7c1c5e8d6ab.png?resizew=158)
拓展探究:
(3)“善思小组”奇想:如图
,将
绕着点
逆时针旋转角度
时,得到
,连接
,
交
于点
,延长
交
于点
,该小组提出一个问题:若
是线段
的中点,
的面积为
,求
的面积,请你思考此问题,直接写出该问题的结果.
问题情境:
在“综合与实践”课上,老师提出如下问题:如图1,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90b40c2b0ab8e1cfe5112d428b4b829f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2689f0ce5ab3467d8214794d8acb2bd6.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/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/10/729d8307-29e4-4e6e-bc21-8b2ea6d9636e.png?resizew=150)
独立思考:
(1)试判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
实践探究:
(2)“聪慧小组”受此问题的启发,将图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbfa1a2af7e38d33634c462300df381f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7199ded47c047792b3147c25467359c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/240ee6902d209dfd156f4ae98e59c077.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3953cec61ac602ce5eb59b7912352179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3b1a5427d8ff23df0f3ec194756c84c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/943712a5e96b16cc15d775cc4687237e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45d30252720ff0a2b1f105523e9aa3b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45d30252720ff0a2b1f105523e9aa3b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/943712a5e96b16cc15d775cc4687237e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/10/b7081816-6ee7-4fae-b917-e7c1c5e8d6ab.png?resizew=158)
拓展探究:
(3)“善思小组”奇想:如图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbfa1a2af7e38d33634c462300df381f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6c96cb3ac8290e09c55d4eb336a8608.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/240ee6902d209dfd156f4ae98e59c077.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/943712a5e96b16cc15d775cc4687237e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45d30252720ff0a2b1f105523e9aa3b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45d30252720ff0a2b1f105523e9aa3b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/943712a5e96b16cc15d775cc4687237e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73afe528350ff17da6fc586fd617495f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4b8503f4706b8321e4e79a87eadea84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71810d999101380a843fd798aa28355c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/10/32502ab9-1768-4e1e-b103-9a422b1bffd2.png?resizew=157)
您最近一年使用:0次
8 . 综合与探究
如图,二次函数
的图象与
轴相交于点
,
,与
轴交于点
,对称轴是直线
,交
轴于点
.
(1)求该二次函数及
所在直线的解析式;
(2)如图1,在线段
上是否存在一点
,使得以
,
,
为顶点的三角形与
相似,若存在,求出点
的坐标;若不存在,请说明理由;
(3)如图2,
是该二次函数图象上位于第一象限上的一动点,连接
分别交
,
轴于点
,
,连接
.若
和
的面积分别为
,
,请直接写出
的最大值.
如图,二次函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a90385c676848de67293e3ed6bc000fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69fff64ee6ea236550185efc7ed1b598.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7720309624a5e413f5e612bd492effe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d599059e6b2c918ab15ee22611b6962.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/5/4fe84046-44cb-4fd2-b878-68b4ca99ca95.png?resizew=325)
(1)求该二次函数及
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)如图1,在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
(3)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.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/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ba8a7ce19548adba34a16080230360d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ff39c7aa648afd1080206c8080ff79e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a38c43d922840f5f7693007beeb62b34.png)
您最近一年使用:0次
9 . 综合与实践
问题情境:
如图1,矩形
和矩形
的顶点
重合,对角线
和
在同一条直线上,点
,
,
和点
,
,
分别都在同一条直线上.
数学思考:
(1)求证:
.
猜想证明:
(2)连接
交
于点
,试猜想
,
与
之间的数量关系,并证明你的猜想.
问题情境:
如图1,矩形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b1f13007c6d134c50004c62dc240707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](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/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
数学思考:
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acd901b235cbfabc4732787c885c59a8.png)
猜想证明:
(2)连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7192e4d245477bf6dafd63e94f955e32.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b315e53c45c1effee544fbef24836a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91188e5c0e22bd4f894e165935cd770a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/5/b817fd45-8aab-46dd-a64b-b458eed90fe3.png?resizew=187)
您最近一年使用:0次
10 . 如图,在等边
中,
是
边上的一点,
于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/4/6770398e-3e3a-42bf-b376-18136e895060.png?resizew=178)
(1)请用无刻度的直尺和圆规在
边上作一点
,使得
;(不写作法,保留作图痕迹,标明字母)
(2)在(
)的条件下,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/824938c27f63ba9b36eaea6cdd389e6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/4/6770398e-3e3a-42bf-b376-18136e895060.png?resizew=178)
(1)请用无刻度的直尺和圆规在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ac698a7465acd65aa99ca0cdc9a6563.png)
(2)在(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e04f260e70d40085e06a42de75eac564.png)
您最近一年使用:0次