1 . (1)当
时,试用分析法证明:
;
(2)已知
,
.求证:
中至少有一个不小于0.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b6c5526947e9bef051bc3bdf7fd186d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2b1411bbc505b5056e68e077d18e06b.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4166972dec0aa3e8694a44eeb941a08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/003fe3cdffd8338cf5766dd287b0c5e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/663a61ad241d5d874c9a9362f0ee917c.png)
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2017-05-03更新
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834次组卷
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5卷引用:【全国百强校】宁夏平罗中学2018-2019学年高二下学期第一次月考数学(文)试题
2 . 如图,在梯形
中,
∥
,
,
,平面
平面
,四边形
是矩形,
,点
在线段
上.
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/c1ef9ef6d0d24be5acaf0fe6afcde188.png)
(Ⅰ)求证:
平面
;
(Ⅱ)当
为何值时,
∥平面
?证明你的结论;
(Ⅲ)求二面角
的平面角的余弦值.
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/68f5ef31f20a4c379bd10a3fb2b3b0c7.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/6d834b46b8ba429f9eed15cfd1eb8dbc.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/731e4b16edfe4950b4ba9640003d5d6b.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/e62eed1cbd894981acfdc2e5ceefb20c.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/499f825f40334c66981cab494efb74cd.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/d65c720a0c2b44dbb01f476c3d5de217.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/68f5ef31f20a4c379bd10a3fb2b3b0c7.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/28858d1fa3e74f6299c575df9a9b523e.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/6a772d000010479fb81c6d5f013b200d.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/1f4ed11a77fb421e989a852d3b3371ba.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/e1acdbac12c14748ac8bb416865a4eab.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/c1ef9ef6d0d24be5acaf0fe6afcde188.png)
(Ⅰ)求证:
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/2641d41d490540b4bab05389115142dd.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/28858d1fa3e74f6299c575df9a9b523e.png)
(Ⅱ)当
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/68636c28fc74406ca34c7967d12a83e7.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/f1aa6ef2b9444e198a0005c40221ec0f.png)
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/7ad087e8e9894940880c88e036f41421.png)
(Ⅲ)求二面角
![](https://img.xkw.com/dksih/QBM/2016/9/23/1573037998727168/1573038004748288/STEM/e2071501b19e4315af7a163d7a878aef.png)
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2016-12-04更新
|
453次组卷
|
2卷引用:2016届宁夏银川唐徕回民中学高三下三模理科数学试卷
3 . 如图,四棱锥
中,底面
是正方形,
平面
,
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2018/5/5/1938553481633792/1940735921700864/STEM/53c9ec8cd2a7424b8c99ed8f8b79aa71.png?resizew=211)
(1)求证:
平面
;
(2)证明:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43d4c42112e0a22f240ce2ae432e5b4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/2018/5/5/1938553481633792/1940735921700864/STEM/53c9ec8cd2a7424b8c99ed8f8b79aa71.png?resizew=211)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373f735f0f04d11f1951eaef1bb78b6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3547a914468b082d8d8741b974a03190.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
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2016-12-04更新
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617次组卷
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7卷引用:宁夏银川三沙源上游学校2019-2020学年高二上学期第二次月考数学(理)试题
4 . 如图,在三棱柱ABC-A1B1C1中,AA1C1C是边长为4的正方形.平面ABC⊥平面AA1C1C,AB=3,BC=5.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/13/4ca3cfb7-fea0-4c1f-b33e-a301806e022c.png?resizew=140)
(Ⅰ)求证:AA1⊥平面ABC;
(Ⅱ)求二面角A1-BC1-B1的余弦值;
(Ⅲ)证明:在线段BC1存在点D,使得AD⊥A1B,并求
的值.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/13/4ca3cfb7-fea0-4c1f-b33e-a301806e022c.png?resizew=140)
(Ⅰ)求证:AA1⊥平面ABC;
(Ⅱ)求二面角A1-BC1-B1的余弦值;
(Ⅲ)证明:在线段BC1存在点D,使得AD⊥A1B,并求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c04c68f1ef1e37534b5bbc7a1f592ef7.png)
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2016-12-02更新
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4629次组卷
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30卷引用:【全国百强校】宁夏银川一中2019届高三第四次月考数学(理)试题
【全国百强校】宁夏银川一中2019届高三第四次月考数学(理)试题2013年全国普通高等学校招生统一考试理科数学(北京卷)(已下线)2014届上海交大附中高三数学理总复习二空间向量与立体几何练习卷2016-2017学年湖北省重点高中联考协作体高二下学期期中考试数学(理)试卷湖北省宜昌市葛洲坝中学2018届高三9月月考数学(理)试题【全国百强校】江苏省泰州中学2017-2018学年高二6月月考数学(理)试题专题11.8 空间向量与立体几何(练)-江苏版《2020年高考一轮复习讲练测》湖南省长沙市长郡中学2017-2018学年高二下学期入学考试数学(理)试题人教A版(2019) 选择性必修第一册 过关斩将 第一章 空间向量与立体几何 专题强化练3 立体几何中的存在性与探究性问题福建省连城县第一中学2020-2021学年高二上学期第一次月考数学试题江西省景德镇一中2020-2021学年高二(2班)上学期期中考试数学试题(已下线)第一章 空间向量与立体几何单元检测(知识达标卷)-【一堂好课】2021-2022学年高二数学上学期同步精品课堂(人教A版2019选择性必修第一册)河北省涞水波峰中学2020-2021学年高二上学期期末数学试题(已下线)专题03 空间向量与立体几何-立体几何中的存在性与探究性问题-2021-2022学年高二数学同步练习和分类专题教案(人教A版2019选择性必修第一册)(已下线)专练9 专题强化练3-立体几何中的存在性与探究性问题-2021-2022学年高二数学上册同步课后专练(人版A版选择性必修第一册)(已下线)期中考试重难点专题强化训练(1)——向量的综合运用-2021-2022学年高二数学单元卷模拟(易中难)(2019人教A版选择性必修第一册+第二册)海南热带海洋学院附属中学2021届高三11月第二次月考数学试题江西省靖安中学2021-2022学年高二上学期第一次月考数学(理)试题苏教版(2019) 选修第二册 名师精选 第六章 空间向量与立体几何云南省弥勒市第一中学2021-2022学年高二上学期第三次月考数学试题安徽省合肥市第八中学2021-2022学年高二下学期平行班开学考理科数学试题河南省濮阳市范县第一中学2021-2022学年高二上学期第二次月考检测数学试题河南省鹤壁市浚县浚县第一中学2021-2022学年高一下学期7月月考数学试题2023版 北师大版(2019) 选修第一册 名师精选卷 第三章 空间向量与立体几何北京市丰台区第十二中学2021-2022学年高二上学期期中数学试题重庆市忠县乌杨中学校2021-2022学年高二上学期期中数学试题云南省曲靖市罗平县第二中学2021-2022学年高二上学期第二次月考数学试题福建省福州市福州中加学校2023-2024学年高二上学期期中数学试题(已下线)第五章 破解立体几何开放探究问题 专题一 立体几何存在性问题 微点1 立体几何存在性问题的解法(一)【基础版】(已下线)【一题多解】存在与否 向量探索
13-14高二下·宁夏银川·期中
5 . 完成反证法证题的全过程.设a1,a2,…,a7是1,2,…,7的一个排列,求证:乘积p=(a1-1)(a2-2)…(a7-7)为偶数.
证明:假设p为奇数,则a1-1,a2-2,…,a7-7均为奇数.因奇数个奇数之和为奇数,故有奇数=_____ =_______ =0.但0≠奇数,这一矛盾说明p为偶数.
证明:假设p为奇数,则a1-1,a2-2,…,a7-7均为奇数.因奇数个奇数之和为奇数,故有奇数=
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6 . 已知数列
的首项
且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27abc0ddb1696ba33720fe25cb57fb75.png)
(1)证明:
是等比数列;
(2)求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8268477a9da05189133a427668aa4c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27abc0ddb1696ba33720fe25cb57fb75.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c895d4ce5ce82ef9b311b9369b4de11.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5816ff5a1585c9b748b13f5b8bd0b6f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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今日更新
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258次组卷
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2卷引用:宁夏回族自治区银川一中2024届高三第三次模拟考试理科数学试题
名校
解题方法
7 . 已知三棱柱
中,
,
,
,
.
平面
;
(2)若
,且P是
的中点,求平面
和平面
所成二面角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df209c58c4cc146ef62100e6d3b068d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f88e7df45acca3fc3d3da3370f0c32bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df00cdf77ed39ca5a0b305861a693142.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7e3c9e7c05de9838c0c5d762720d3ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1752434352ecb9834eaba9c63fc9abe2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea848cd2aa3a464618020475097949fc.png)
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名校
8 . 在四棱锥
中,平面
平面
,
∥
,
,
,
.
;
(2)若
为等边三角形,求直线PC与平面PBD所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.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/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/328a79d5f45baa162bf1e6bb2d4fc6c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55e1de129bfc451f4c7160cc50666ad8.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
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名校
解题方法
9 . 已知函数
,
的最大值是
.
(1)求
的值;
(2)若
,且
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b579f06fb171212d46ff13b34c799cbc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61a895920706f9f39d1b48ab42e09923.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2684b72f9f38f5046c8ecd4280b7b14b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bf140abb1d26b46f979f693fe71e56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b56bfd6d391021a360e4b214de44b33c.png)
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2024-06-11更新
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222次组卷
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5卷引用:宁夏回族自治区石嘴山市平罗县平罗中学2023-2024学年高三下学期第五次模拟考试数学(文)试题
名校
解题方法
10 . 已知函数![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc7487ccd8c49ed91c74dc95378ef19.png)
(1)求不等式
的解集;
(2)已知
的最小值为
,且正实数
满足
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc7487ccd8c49ed91c74dc95378ef19.png)
(1)求不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa18838a13fda4e45612c32cdf98b71.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7863b54185da5a3f1a765e1aa0577e76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632244ea6931507f8656e1cc3437d392.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d86be2de99fbf7f99cd54ab399146b00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dec73b1dcc592192eb2f54448b8c949a.png)
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2卷引用:宁夏回族自治区银川九中、平罗中学、贺兰二高、西吉中学2024届高三第四次模拟考试联考数学(文)试题