如图,已知P是
外一点.用两种不同的方法过点P作
的一条切线.要求:
(1)用直尺和圆规作图;
(2)保留作图的痕迹,写出必要的文字说明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(1)用直尺和圆规作图;
(2)保留作图的痕迹,写出必要的文字说明.
2021·江苏南京·中考真题 查看更多[10]
江苏省南京市2021年中考数学试卷(已下线)押江苏南京中考数学第19-25题(几何证明与锐角三角函数的实际应用)-备战2022年中考数学临考题号押题(江苏南京专用)(已下线)第05练 确定圆的条件-2022-2023学年九年级数学上册课后培优分级练(苏科版)(已下线)专题15 三角形解答题-三年(2020-2022)中考数学真题分项汇编(江苏专用)(已下线)专题19 圆解答题-三年(2020-2022)中考数学真题分项汇编(江苏专用)(已下线)专题2.13 确定圆的条件(直通中考)-2023-2024学年九年级数学上册基础知识专项突破讲与练(苏科版)(已下线)第4讲 作图题山东省济宁市济宁学院附属中学2023-2024学年九年级上学期第四次月考数学试题江苏省宿迁市沭阳如东实验学校2023-2024学年九年级上学期11月检测数学试题(已下线)专题08 几何作图问题1-2024年中考数学二轮热点题型归纳与变式演练(江苏专用)
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【推荐1】如图,在□ABCD 中,以点 A 为圆心,AB 长为半径画弧交 AD 于点 F,再分别以点 B、F 为圆心,大于
BF 的相同长为半径画弧,两弧交于点 P,连接 AP 并延长交 BC 于点 E,连接 EF.
(1)根据以上尺规作图的过程,证明四边形 ABEF 是菱形;
(2)若菱形 ABEF 的边长为 2,AE= 2
,求菱形 ABEF 的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
(1)根据以上尺规作图的过程,证明四边形 ABEF 是菱形;
(2)若菱形 ABEF 的边长为 2,AE= 2
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
![](https://img.xkw.com/dksih/QBM/2020/4/7/2436262770081792/2437004411076609/STEM/b8f9c44d80084f75a5825d8056f5a284.png?resizew=241)
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【推荐2】如图,直线AB、CD相交于点O,∠BOD=45°,按下列要求画图并回答问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/a4aa880d-0fdb-4b31-8eee-0a0895e2d3c7.png?resizew=152)
(1)利用三角尺,在直线AB上方画射线OE,使OE⊥AB;
(2)利用圆规,分别在射线OA、OE上截取线段OM、ON,使OM=ON,连接MN;
(3)利用量角器,画∠AOD的平分线OF交MN于点F;
(4)直接写出∠COF= °.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/a4aa880d-0fdb-4b31-8eee-0a0895e2d3c7.png?resizew=152)
(1)利用三角尺,在直线AB上方画射线OE,使OE⊥AB;
(2)利用圆规,分别在射线OA、OE上截取线段OM、ON,使OM=ON,连接MN;
(3)利用量角器,画∠AOD的平分线OF交MN于点F;
(4)直接写出∠COF= °.
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【推荐1】如图1,点
不在锐角
的各边和顶点上,若满足
,则称点
为“点
的和谐点”,其中,当点
在
的内部时,点
称为“点
的内和谐点”,当点
在
的外部时,点
称为“点
的外和谐点”.
每个顶点的“和谐点”,称为“
的和谐点”.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/26/fde1017b-6ba2-4f50-9887-05e7c3beb27d.png?resizew=376)
(1)在图1中,点
的外和谐点有几个?并请在图1中用圆规和直尺作出来;(要求:不写作法,保留作图痕迹)
(2)如图2,有一个格点锐角
,已知网格的边长为1.
①已知格点
是点
的一个和谐点,请找出点
的其他所有的和谐点(要求:是格点),并标上字母
,
,……;
②已知格点
是
的“外和谐点”,求以
、
、
、
四点构成的四边形的面积的所有可能的取值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b927e91746b5526b567c837782fc3fb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/26/fde1017b-6ba2-4f50-9887-05e7c3beb27d.png?resizew=376)
(1)在图1中,点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)如图2,有一个格点锐角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
①已知格点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
②已知格点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.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/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
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【推荐2】阅读理解,自主探究:“一线三垂直”模型是“一线三等角”模型的特殊情况,即三个等角角度为
,于是有三组边相互垂直.所以称为“一线三垂直模型”.当模型中有一组对应边长相等时,则模型中必定存在全等三角形.
中,
,
,过点C作直线
,
于D,
于E,求证:
;
(2)问题探究:如图2,在等腰直角
中,
,
,过点C作直线
,
于D,
于E,
,
,求
的长;
(3)拓展延伸:在平面直角坐标系中,
,点B在第一、第三象限的角平分线l上.点C在y轴上,
为等腰直角三角形;
①如图3,当
时,求点C的坐标;
②直接写出其他符合条件的C点的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b10134e7a46e6f6f7cb9d5e2371727d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c1c122603b60b6f1a1334ddb56c3fb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c182a9d9fd0a7023b710cd671d9468e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e57c76abca2467af86f45da0fec08cb.png)
(2)问题探究:如图2,在等腰直角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b10134e7a46e6f6f7cb9d5e2371727d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ccd5c41c921836b50f8e18abfdc5df3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31b2cc1d0bfd22c88286880b9da1f6f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6520b788483e37532afb588503cd2bad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bd688a3ee94e713e35e4d03163badb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
(3)拓展延伸:在平面直角坐标系中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0bfed05471d0b562128059cf73763be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
①如图3,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3493ae59c386883c6a7eab670ee251c7.png)
②直接写出其他符合条件的C点的坐标.
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【推荐3】
(1)【活动背景】在鹿鸣成长课程中,同学们探究了一类“三等分线段、角”的问题.如图,在矩形
的边
和
上分别取点E、F,且
,连接
、
交于点O,将边
沿着过点O的直线折叠,使得点A、D分别落在
和
上,试说明:点Q是边
的三等分点.
,点E是
的中点,请用无刻度直尺和圆规作平行四边形
,使得
.(不写作法参保留作图痕迹)
上一点,用尺规作出
,
后,将直尺一端放在点O处,不断转动直尺与
、
交干点M、N,当
与
满足某种数量关系时,即可得到
,试猜想
与
的数量关系并证明.
,若
,请直接写出k的取值范围.
(1)【活动背景】在鹿鸣成长课程中,同学们探究了一类“三等分线段、角”的问题.如图,在矩形
![](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/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d78e03251a5de00fe4b8684cd258d4d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.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/900b844294e8c07ea9a858adb845121c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c51c25b65a37b676ae3c3b71c29f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/786080c82db1e1d3ec6367397aa63220.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f46d004eb8bdd7de7816ee48dfbce038.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdc93e193fad261689949a52819753f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3377b91d6810fbb7076ebbab2a15911.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdc93e193fad261689949a52819753f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e61956af44b7a26c5c3a0d4c68160a88.png)
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【推荐1】猜想与证明:小强想证明下面的问题:“有两个角(图中的∠B 和 ∠C)相等的三角形是等腰三角形”.但他不小心将图弄脏了,只能看见图中的∠C和边BC.
![](https://img.xkw.com/dksih/QBM/2020/11/25/2600660893147136/2603619544465408/STEM/c2eab0d8-6b02-4e11-9333-4080b14e485b.png?resizew=332)
(1)请问:他能够把图恢复成原来的样子吗?若能,请你帮他写出至少两种以上恢复的方法,并在备用图上恢复原来的样子。
![](https://img.xkw.com/dksih/QBM/2020/11/25/2600660893147136/2603619544465408/STEM/329eba02-d078-41be-a7cd-046f9c92659b.png?resizew=406)
方法1:
方法2:
方法3:
(2)你能够证明这样的三角形是等腰三角形吗?(至少用两种方法证明)
![](https://img.xkw.com/dksih/QBM/2020/11/25/2600660893147136/2603619544465408/STEM/c2eab0d8-6b02-4e11-9333-4080b14e485b.png?resizew=332)
(1)请问:他能够把图恢复成原来的样子吗?若能,请你帮他写出至少两种以上恢复的方法,并在备用图上恢复原来的样子。
![](https://img.xkw.com/dksih/QBM/2020/11/25/2600660893147136/2603619544465408/STEM/329eba02-d078-41be-a7cd-046f9c92659b.png?resizew=406)
方法1:
方法2:
方法3:
(2)你能够证明这样的三角形是等腰三角形吗?(至少用两种方法证明)
![](https://img.xkw.com/dksih/QBM/2020/11/25/2600660893147136/2603619544465408/STEM/edc2b13c-3d76-490d-99f7-28bd2e612f4b.png?resizew=313)
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【推荐2】Rt△ABC中,∠C=90°,∠A=30°,BC=a.以AB为斜边,在AB所在直线的右侧作一个等腰Rt△ABD.
(1)用尺规作图,保留作图痕迹;
(2)请尝试用两种不同的方法计算四边形ACBD的面积,从而推导出sin75°=
.
(1)用尺规作图,保留作图痕迹;
(2)请尝试用两种不同的方法计算四边形ACBD的面积,从而推导出sin75°=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e34f8ef860307d4c133b918472f3200.png)
![](https://img.xkw.com/dksih/QBM/2020/9/30/2560655733923840/2566150110003200/STEM/469c949bdbc242bd9e67cb3e54b123b4.png?resizew=113)
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【推荐1】在
中,已知
为直径,点
是弧
上一点,弦
,且
弦
,连
交
于点
,点
在
的延长线上,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/26/bbdc6a72-a238-48aa-b26c-fcf9849255b5.png?resizew=161)
(1)求证:
是
的切线;
(2)若
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.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/066cd386723885c535ea720f5817847a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8d2d217e9bcd059908f117dfc4d4259.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57870545d142e535da173cd118111a7b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/26/bbdc6a72-a238-48aa-b26c-fcf9849255b5.png?resizew=161)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5adb5eb60ae4435a12d93854066298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b13d69aa12612e5eeab689acd7226d71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c8ffe24cf9f327aeb241225ab15ab1a.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐2】已知在
中,
,
,
,以边
为直径作
,与
边交于点
,点
为边
的中点,连接
.
是
的切线;
(2)点
为直线
上任意一动点,连接
交
于点
,连接
.
①当
时,求
的长;
②求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07160f14b3b453bebb64cb2bf96dc85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4494a85de0be0b97a69348115aef8513.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15a424b50eaeafa6f302ffd95476cb86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15a424b50eaeafa6f302ffd95476cb86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(2)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f53330c107f8245290a5a42c3d356acd.png)
①当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80d7c4fb5da711e6a80f9d2b9fb8dbd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
②求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41f30ab0bc020502b3b89ffe1c1a52c5.png)
您最近一年使用:0次