23-24高二上·上海·课后作业
1 . 请指出下列各题用数学归纳法证明过程中的错误.
(1)设
为正整数,求证:
.
证明:假设当
(
为正整数)时等式成立,即有
.
那么当
时,就有![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b265260b1c40af006ba6f66a11ed576.png)
.因此,对于任何正整数
等式都成立.
(2)设
为正整数,求证:
.
证明:①当
时,左边
,右边
,等式成立.
②假设当
(
,
为正整数)时,等式成立,即有
,
那么当
时,由等比数列求和公式,就有
,等式也成立.
根据(1)和(2),由数学归纳法可以断定
对任何正整数
都成立.
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b502d9c57239d9f42fdf849878018061.png)
证明:假设当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef7ca2b3e8061384501f668e59696a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d8963d68c930f5b28cc8b92c43d469b.png)
那么当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63ba21f3d0cfc86d40e2e06446623ce0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b265260b1c40af006ba6f66a11ed576.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced66f7e147b6276e1ce9e2b67510141.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8883d7d43d3f61a771d16537c52ac451.png)
证明:①当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c87b351f16728b0023fd63678f8103c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90bae886c8ab958aa4c693bf8e0627d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90bae886c8ab958aa4c693bf8e0627d.png)
②假设当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef7ca2b3e8061384501f668e59696a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2397df3279607612ea3cbef101ee0bf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a439aebc27b99718f09e1dff2649482f.png)
那么当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63ba21f3d0cfc86d40e2e06446623ce0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b838d781d5ce98ddcc08af86c1f27ae.png)
根据(1)和(2),由数学归纳法可以断定
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8883d7d43d3f61a771d16537c52ac451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
名校
解题方法
2 . 已知函数
与
的定义域为R,若对任意区间
,存在
且
,使
,则
是
的生成函数.
(1)求证:
是
的生成函数;
(2)若
是
的生成函数,判断并证明
的单调性;
(3)若
是
的生成函数,实数
,求
的一个生成函数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4133958c09fdd82cda8838c9cf46ccda.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71717fb069fa0f5a1d196b6484618351.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92c035964f2f9d1c84a91cc651fb5e4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b23eea271d1b00e358ca6dc048e8134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fad236fddf9598b319a1acd223a9269.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4133958c09fdd82cda8838c9cf46ccda.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d761c4444f5eac17133caaf19d6b9ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01f4b87b2b2d6297cb330a6aa6a96c95.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c18e7d848da79e20188ed6a0225a0c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4133958c09fdd82cda8838c9cf46ccda.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4133958c09fdd82cda8838c9cf46ccda.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4133958c09fdd82cda8838c9cf46ccda.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20849c00c47cbdc43f18d53341b6c4e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5aed37e8318fb8ca63e19e06dbcdd791.png)
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2023-05-05更新
|
572次组卷
|
4卷引用:上海交通大学附属中学2022-2023学年高一下学期期中数学试题
上海交通大学附属中学2022-2023学年高一下学期期中数学试题湖南省长沙市明德中学2022-2023学年高一下学期5月月考数学试题(已下线)第3课时 课后 函数的单调性(完成)(已下线)5.2.2 函数的单调性-数学同步精品课堂(沪教版2020必修第一册)
解题方法
3 . (1)已知直线
与抛物线
交于
,
两点,直线l与x轴相交于点
,求证:
;
(2)试将第(1)题中的命题加以推广,使得第(1)题中的命题是推广后得到的特例,并证明推广后得到的命题正确.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cbc3a148fea86d30909dee2022fb384.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10f4123c19136d3a4dc040dce8e34e14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f021572c9349d56120b7094c34126623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/278c3598da951b73b53dc4a3929e65f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9393d79bf424855cae6938d125b201f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59a65a75e6ec85f8fc5a2758edfef95c.png)
(2)试将第(1)题中的命题加以推广,使得第(1)题中的命题是推广后得到的特例,并证明推广后得到的命题正确.
您最近一年使用:0次
解题方法
4 . 计算三角比时,我们常会用到对称思想来解答.
例如:求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/360fd195a7deaaa81b38a69c4ffdc108.png)
证明:设![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e0bd9baaf6e9f693958259bf2c3d46.png)
,∴
,
而![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1eed68d61dd8451c0f418bd29af01f3b.png)
∴![](https://staticzujuan.xkw.com/quesimg/Upload/formula/360fd195a7deaaa81b38a69c4ffdc108.png)
根据上述证法,计算下面两式的值:
(1)
;
(2)
.
例如:求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/360fd195a7deaaa81b38a69c4ffdc108.png)
证明:设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e0bd9baaf6e9f693958259bf2c3d46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a0064366ea74d49bd24afd69721fb2a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc87ab4dbfdd85d997b2e28b0d789e41.png)
而
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1eed68d61dd8451c0f418bd29af01f3b.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/360fd195a7deaaa81b38a69c4ffdc108.png)
根据上述证法,计算下面两式的值:
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf8e62fba29d1ee28d5ad3f873a635b3.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797f8b8f08e427972eaf62ec8fc249c2.png)
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5 . 已知函数
的定义域为
,
为大于
的常数,对任意
,都满足
,则称函数
在
上具有“性质
”.
(1)试判断函数
和函数
是否具有“性质
”(无需证明);
(2)若函数
具有“性质
”,且
,求证:对任意
,都有
;
(3)若函数
的定义域为
,且具有“性质
”,试判断下列命题的真假,并说明理由,
①若
在区间
上是严格增函数,则此函数在
上也是严格增函数;
②若
在区间
上是严格减函数,则此函数在
上也是严格减函数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f5a90aeba435af22d6bcdb7b91650b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e02cab1add26335b3cb43d5b54c7c853.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/803b4afffc6c71c6d2c3d8dff0102189.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f5a90aeba435af22d6bcdb7b91650b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(1)试判断函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b161347f6a2fcfd9bf0acf1e8a03fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c57e815c01a412466a6aa12d3e883a77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(2)若函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9a3c7303b5dccb55a94db4abb410932.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd4613271f782a90ab580131d09d03d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a64646b34d48e913836a220e24460734.png)
(3)若函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad2edd8edcb21bd41584daf9bb95a5c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad2edd8edcb21bd41584daf9bb95a5c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
您最近一年使用:0次
2023-01-12更新
|
630次组卷
|
6卷引用:上海市闵行区2022-2023学年高一上学期期末数学试题
上海市闵行区2022-2023学年高一上学期期末数学试题(已下线)专题10 指数及指数函数压轴题-【常考压轴题】(已下线)第五章 函数的概念、性质及应用(压轴必刷30题9种题型专项训练)-【满分全攻略】(沪教版2020必修第一册)(已下线)期末真题必刷压轴60题(10个考点专练)-【满分全攻略】(沪教版2020必修第一册)(已下线)期末真题必刷压轴60题(22个考点专练)-【满分全攻略】(人教A版2019必修第一册)(已下线)第四章 指数函数与对数函数-【优化数学】单元测试能力卷(人教A版2019)
解题方法
6 . 已知函数
,
的表达式分别为
,
,
.
(1)证明:函数
在区间
上是严格增函数;
(2)求函数
的最小值及相应
的取值集合;
(3)若函数
,
且
对一切
恒成立,则称
的图像在
的图像的上方.求证:当
时,
的图像在
的图像的上方.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a1cfb60420ff7e72c1b9d64f69ae063.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75f46f632f2a710b3617f69c3d31ba00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cac43c22b4da6e232f4891d71f0bbb5.png)
(1)证明:函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d133cf04971ea0116f2f54982f4e92b.png)
(2)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be1ce3f01e2b6364f9a9fdaf197d5e29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(3)若函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83f3574c440135b1e8d33f9662e7e883.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e915b67f8f747698b8b46d37bc453667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b197c6e77b06afde23727f9f498e9ffe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a57996290794e082b21d8f1dfc322a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2183ba00d69af06d9a950469b38cfe4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0eb7df298a9364b36e079a61caec815c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6442958bd5b5f8ac690b33ea0bccdd0f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be1ce3f01e2b6364f9a9fdaf197d5e29.png)
您最近一年使用:0次
7 . (1)求证:
;
(2)求证:
;
(3)若m、n、r均为正整数,试证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/588855663a97d8fc98e41368c9f0c887.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/724a6dd2bb85b676a9ddbcb4d8ede156.png)
(3)若m、n、r均为正整数,试证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6ca3166112603878ea3d79170b7632d.png)
您最近一年使用:0次
解题方法
8 . 如图,在直角梯形
中,
,
,
,并将直角梯形
绕AB边旋转至ABEF.
平面ADF;
(2)求证:直线
平面ADF;
(3)当平面
平面ABEF时,再从条件①、条件②、条件③这三个条件中选择一个作为已知,使平面ADE与平面BCE垂直.并证明你的结论.
条件①:
;
条件②:
;
条件③:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6045266f6db39e41b7abde762d9e9a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
(2)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11d27ff0b39832f094ec51e28721d739.png)
(3)当平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf9a6db3571fa57bfa2d5e4d44c51b3.png)
条件①:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6166b9a5437671bcba31e17c375eb39.png)
条件②:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f4aca5534bce25acaeb7379deed8f8f.png)
条件③:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c182a9d9fd0a7023b710cd671d9468e7.png)
您最近一年使用:0次
2022-07-08更新
|
1285次组卷
|
11卷引用:7.2 空间几何中的垂直(精练)
(已下线)7.2 空间几何中的垂直(精练)(已下线)7.1 空间几何中的平行与垂直(精讲)(已下线)高考新题型-立体几何初步(已下线)8.6.1 空间直线、平面的垂直(精练)-2022-2023学年高一数学一隅三反系列(人教A版2019必修第二册)(已下线)模块三 专题9(劣构题)拔高能力练(北师大版)(已下线)模块三 专题9(劣构题)基础夯实练(人教B)(已下线)模块三 专题9(劣构题)拔高能力练人教A版)(已下线)2023年高考全国乙卷数学(理)真题变式题16-20(已下线)模块三 专题10(劣构题)拔高能力练(苏教版)北京市丰台区2021-2022学年高一下学期期末练习数学试题(已下线)专题06 空间中点线面的位置关系6种常考题型归类(1)-期期末真题分类汇编(北京专用)
解题方法
9 . 已知抛物线
,
,
是C上两个不同的点.
(1)求证:直线
与C相切;
(2)若O为坐标原点,
,C在A,B处的切线交于点P,证明:点P在定直线上.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fa2c731aaa4005382d5b4324e29fbb0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9fb1a589404b101361fab4a264af920.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d4adb1a0c5fbcaa7cb61b2febdb7db3.png)
(1)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d031516b8b9572a1973e44004a30493a.png)
(2)若O为坐标原点,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eb512456bcc994ea2354e9525d3f282.png)
您最近一年使用:0次
2022-07-25更新
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1234次组卷
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6卷引用:专题3-6 抛物线综合大题归类(讲+练)-【巅峰课堂】2023-2024学年高二数学热点题型归纳与培优练(人教A版2019选择性必修第一册)
(已下线)专题3-6 抛物线综合大题归类(讲+练)-【巅峰课堂】2023-2024学年高二数学热点题型归纳与培优练(人教A版2019选择性必修第一册)江西省名校联考2023届高三7月第一次摸底测试数学(理)试题抛物线的综合问题(已下线)专题6 判断位置关系的运算(基础版)(已下线)专题3.14 直线与抛物线的位置关系-重难点题型检测-2022-2023学年高二数学举一反三系列(人教A版2019选择性必修第一册)(已下线)专题05 抛物线8种常见考法归类(2)
21-22高一·湖南·课后作业
解题方法
10 . 证明不等式:
(1)若
,
,
,
都是正数,求证:
;
(2)若
,
,
是非负实数,则
;
(3)若
,
是非负实数,则
;
(4)若
,
,则
.
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2e7387a3fbab6508695365955f55258.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2d92a6b95fdfdedb405447340293bdc.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/727ff3ac24b506706045956c16336f94.png)
(4)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19339e3904e9541ff26b30ae5f1242b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4f58b9bc974b789928f6490acb43fb3.png)
您最近一年使用:0次