如图,已知直线
交
于
、
两点,
是
的直径,点
为
上一点,且
平分
,过
作
,垂足为
.
(1)求证:
为
的切线;
(2)若
,
的直径为20,求线段
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.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/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.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/b8e2c17d4d575f9c14180c5648b0d6dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0530f462e5ec1e58c46e1f7644d0cc21.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f3ba8b214034c287276f4966069d95e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/27/4c70366c-dce4-4865-8006-43dec55d2e94.png?resizew=160)
更新时间:2020-10-27 21:26:51
|
相似题推荐
解答题-问答题
|
较难
(0.4)
【推荐1】(1)如图①,
与
均是等腰直角三角形,
,
,
,线段
、
交于点
.则
______.
(2)如图②,
是等腰直角三角形,
,
,延长
至点
,使
,以
为直角边在
的左侧作等腰直角
,使得
,
,连接
,求线段
的长.
(3)如图③,
为等腰直角三角形,
,
,在
的左侧作
,使得
,
,
,连接
,求线段
的长.
![](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/26813466e2ee49a493881a4384fc8748.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/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6fdecc899f66d582f609fa88de9aa54.png)
(2)如图②,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/321f96c4f808afe67cf565ca74ae0351.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/120ac801b06f7c609d5dd8975e701b36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7c50d6d16f99c65005dfb950c30d760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
(3)如图③,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/267ace52b64e1e7dfc5211e033255b7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a22b02f6c8636152aeb62d191251e931.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/321f96c4f808afe67cf565ca74ae0351.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/5/4dcb7073-0e8c-443b-8b56-612f5855c20a.png?resizew=404)
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【推荐2】在平面直角坐标系中,抛物线y=mx2﹣2mx﹣3m与x轴交于A、B两点(点A在点B左侧),与y轴交于点C,连接AC,BC,将△OBC沿BC所在的直线翻折,得到△DBC,连接OD.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/22/4a79a348-60f7-4950-bc94-a56eebc43f7c.png?resizew=234)
(1)点A的坐标为 ,点B的坐标为 .
(2)如图,若点D落在抛物线的对称轴上,且在x轴上方,求抛物线的解析式.
(3)设△OBD的面积为S1,△OAC的面积为S2,若S1=
S2,求m的值.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/22/4a79a348-60f7-4950-bc94-a56eebc43f7c.png?resizew=234)
(1)点A的坐标为 ,点B的坐标为 .
(2)如图,若点D落在抛物线的对称轴上,且在x轴上方,求抛物线的解析式.
(3)设△OBD的面积为S1,△OAC的面积为S2,若S1=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c0874f019492261eb175bdcc08c189d.png)
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名校
【推荐1】如图1,直线
与x轴,y轴分别交于A,B两点,
交于点C,直线
与y轴交于点G.平移线段
,点B,C的对应点
、
分别在直线
和y轴上,连接
.
(2)若
,求点C的坐标;
(3)如图2,作点E关于直线
的对称点F,连接
,是否存在四边形
是平行四边形的情况,若存在;求出k的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7211c51b07de22b644df6dde301be330.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01abbd5d3165c047f400f48f5f5ccf51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46f6872ffb1934339c53c2c2282d5889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.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/46f6872ffb1934339c53c2c2282d5889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f135ae4531e59a3c5a7c1e475a5e8934.png)
(3)如图2,作点E关于直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2319a01218514917e446dfc807a625ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce407147ab09385103172602793b2e53.png)
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【推荐2】如图,在四边形ABCD中,AD
BC,AD=3,CD=5,AB=4
,∠B=45°,动点M从点B出发沿线段BC以每秒1个单位长度的速度向终点C运动;同时动点N从点D出发沿线段DC- CB向终点B运动.设运动的时间为t秒.
(2)如果当四边形ABMD是平行四边形时,点M与点N恰好相遇,求点N的运动速度:
(3)在(2)的条件下,求出t为何值时,以点A、M、N、D为顶点的四边形是平行四边形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
(2)如果当四边形ABMD是平行四边形时,点M与点N恰好相遇,求点N的运动速度:
(3)在(2)的条件下,求出t为何值时,以点A、M、N、D为顶点的四边形是平行四边形.
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【推荐3】数学活动课上,同学们开展了以折叠为主题的探究活动,如图1.已知矩形纸片
,其中
,
(a为常数).
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/19/4bc3b779-b982-4b60-8501-bdbfa43ba086.png?resizew=291)
(1)操作判断
将矩形纸片
按图1折叠,使点B落在
边上的点E处,判断四边形
的形状,并说明理由.
(2)探究发现
将图1的纸片展平,把四边形
剪下来如图2,取
边的中点M,将
沿
折叠得到
,延长
交
于点N,求
的周长(用含a的代数式表示).
(3)拓展应用
改变图2中点M的位置,令点M为射线
上一动点,按照(2)中方式将
沿
折叠得到
,
所在直线交
于点N,若点N为
的三等分点,请直接写出此时
的长(用含a的代数式表示).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d42e97eee705d164e6ac6de9ecd6d1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/060d350e824e9b1700696000d3d6e4a2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/19/4bc3b779-b982-4b60-8501-bdbfa43ba086.png?resizew=291)
(1)操作判断
将矩形纸片
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bedde879f99aed69d745d5ec8fe62084.png)
(2)探究发现
将图1的纸片展平,把四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e41c2d7ae6aaf6d91129ed5221a415a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/735056c174e8dd7906257a2a50a962a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f68d65ed39a9dfd09c5b907b5de6b144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b46c607b3deac746c0ef3389ad8f65c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73c8f5ba45ee757675b708a3b9bc3c2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3184cd468586362043f15d3964991725.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c0e1c17a2c9feaa4bd0639ffaa19f9.png)
(3)拓展应用
改变图2中点M的位置,令点M为射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/735056c174e8dd7906257a2a50a962a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f68d65ed39a9dfd09c5b907b5de6b144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b46c607b3deac746c0ef3389ad8f65c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73c8f5ba45ee757675b708a3b9bc3c2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3184cd468586362043f15d3964991725.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9be7fa11b9444524663354ed84792e73.png)
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解答题-证明题
|
较难
(0.4)
【推荐1】如图,在
中,
,以斜边
上的中线
为直径作
,分别与
交于点
.
(1)过点
作
于点
,求证:
是
的切线;
(2)连接
,若
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfa8cee7d2463f6f7d352e8b65f47cf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/571ef38fc225d102bcd4f35bab70078c.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/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8ed1fce01430ae31294c29d626626f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6670479a0083dd2dfd5ad55b47b1ab6.png)
(1)过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfc936d478f47c519ce4aea86dd1e942.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5d8e33929752b1cb4dd36ee9b98b45d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(2)连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be2e2c0d4ac2bd79f6cea7a9b1a50662.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2850bc7459020ef18f580b0b9a2a68fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://img.xkw.com/dksih/QBM/2020/2/20/2403100077047808/2403319876567040/STEM/8579897344c347b2a04e0339dd10a3ef.png?resizew=294)
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真题
名校
【推荐2】在
中,
是斜边
的中点,将线段
绕点
旋转至
位置,点
在直线
外,连接
.
的大小;
(2)已知点
和边
上的点
满足
.
(ⅰ)如图2,连接
,求证:
;
(ⅱ)如图3,连接
,若
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b66a5b7813e902306477f91f9f4084cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be2e2c0d4ac2bd79f6cea7a9b1a50662.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/28a77aa6c27acfffcc601d9ca7e6d4c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/868ff1350bd72625328c85c3097cd85e.png)
(2)已知点
![](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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c52b7d805780d1e59c836176af78733.png)
(ⅰ)如图2,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/532aece6cfd67e2a97977eed978dbf2b.png)
(ⅱ)如图3,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83966f476aa939c554e4286bc027823a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4953f64aead21c2a2e50a248d88c5a07.png)
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
【推荐1】如图,四边形ABCD是平行四边形,以AB为直径的⊙O经过点D,E是⊙O上一点,若⊙O的直径为6cm,且∠AED=45°.
![](https://img.xkw.com/dksih/QBM/2017/3/28/1653745172152320/1715851367759872/STEM/ace05a68b2b9481d8c520cc5ac740eff.png?resizew=187)
(1)判断CD与⊙O的位置关系,并说明理由;
(2)求图中阴影部分的面积;
(3)若EF=1cm,求DF的长.
![](https://img.xkw.com/dksih/QBM/2017/3/28/1653745172152320/1715851367759872/STEM/ace05a68b2b9481d8c520cc5ac740eff.png?resizew=187)
(1)判断CD与⊙O的位置关系,并说明理由;
(2)求图中阴影部分的面积;
(3)若EF=1cm,求DF的长.
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐2】如图,已知AB是
的直径,C是
上的一点,D是AB上的一点,
于D,DE交BC于F,且
.
![](https://img.xkw.com/dksih/QBM/2022/5/18/2982011751088128/2983526844088320/STEM/2471ecb4-e29c-49a8-95a9-c459647aba1b.png?resizew=152)
(1)求证:EC是
的切线;
(2)若
,圆的半径
,______,求切线EC的长.
给出下列条件:①
;②
;③
;
请在上面三个条件中选择一个能解决上述问题的条件填到上面的横线上(填序号),并解决该问题.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32c38dfd14dde969702dff97ef2270f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fa1b5b6051d500fe6c6f1c19c7ee49f.png)
![](https://img.xkw.com/dksih/QBM/2022/5/18/2982011751088128/2983526844088320/STEM/2471ecb4-e29c-49a8-95a9-c459647aba1b.png?resizew=152)
(1)求证:EC是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7eb3d1070981fed5ca65a34bb2282e6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b42602dabcdc7bdaba0ee0af37d71f0.png)
给出下列条件:①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07140f277a35733d8c97577ccdd4e3ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67ee48d9a0a0055fba322505a6c1cdfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de28d337fb56eb2417a4902294545905.png)
请在上面三个条件中选择一个能解决上述问题的条件填到上面的横线上(填序号),并解决该问题.
您最近一年使用:0次