名校
1 . 在
中,角A,B,C对应边长分别为a,b,c.
(1)设
,
,
是
的三条中线,用
,
表示
,
,
;
(2)设
,
,求证:
.(用向量方法证明)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abcb5d89b04570ceda2c29e11cb27a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af5f1b06a56fc382feed28e01f1ad102.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/304a7f07db2ec637baadf8f0ab91c85c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f33a112e9728d7b560199765c815f69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7449e9c8e2278360620b32cb91ee555c.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f89deb952f57f4b3fa4887b098b7b91.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/999bffc53cd88451b784bf119568ec54.png)
您最近一年使用:0次
2 . 对于正整数集合
(
),如果任意去掉其中一个元素![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
之后,剩余的所有元素组成的集合都能分为两个交集为空集的集合,且这两个集合的所有元素之和相等,就称集合A为“可分集合”;
(1)判断集合
和
是否是“可分集合”(不必写过程);
(2)求证:四个元素的集合
一定不是“可分集合”;
(3)若集合
是“可分集合”,证明:
为奇数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3a3f24673b6e954db3a8b229d8c4564.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7694f1219e3a480e81f62b29915b03d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cecc3d59296521ff4e1edc78a4ea67d7.png)
(1)判断集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e9859aa908844a32c0e1e069a046727.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a44d462b5c1b7b7ea6c0f36e5cab65b9.png)
(2)求证:四个元素的集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a784e0ba1c17aba6990123fe39b89114.png)
(3)若集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffbfa3e226e067ec597ebf0bbc2e87d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
名校
3 . 对于正整数集合
,如果去掉其中任意一个元素
之后,剩余的所有元素组成的集合都能分为两个交集为空集的集合,且这两个集合的所有元素之和相等,就称集合
为“平衡集”.
(1)判断集合
是否是“平衡集”并说明理由;
(2)求证:若集合
是“平衡集”,则集合
中元素的奇偶性都相同;
(3)证明:四元集合
,其中
不可能是“平衡集”.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffbfa3e226e067ec597ebf0bbc2e87d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62c4392f75c09edaec2e70c9eccb2b85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(1)判断集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e5f6cb6141a374d04b6a14a1b27e282.png)
(2)求证:若集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(3)证明:四元集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a784e0ba1c17aba6990123fe39b89114.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59a3f266cb6beee27f3d831c1169d3d2.png)
您最近一年使用:0次
4 . 如图,在多面体
中,四边形
是边长为
的正方形,平面
平面
,
,
,
.
(1)求证:
平面
;
(2)求平面
与平面
夹角的余弦值;
(3)线段
上是否存在点
,使得
平面
?若存在,指出点
的位置并证明;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79c1acdd27cebb11e0266464b03b3afb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8139d9fd5c670c91aa7dc485366dd1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8e41916523511064a97de39b0f2b323.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5e5c1b19afa9febdef52968bd55a320.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/22/886d39e6-9812-4d18-a1a9-4db4c413ccc3.png?resizew=136)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e56fdf217165748fafe938b64fa08179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(3)线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12d8677ae5ca7acf874d93789425d172.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
您最近一年使用:0次
2023-11-03更新
|
442次组卷
|
2卷引用:北京市顺义区第二中学2023-2024学年高二上学期期中考试数学试题
名校
5 . 如图,在四棱锥P-ABCD中,底面ABCD是平行四边形,∠ACB=90°,PA⊥平面ABCD,
,
,F是BC的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/03bf86d4-be07-4242-89cf-a390e5adc0b0.png?resizew=226)
(1)求证:AD⊥平面PAC;
(2)试在线段PD上确定一点G,使
∥平面PAF,请指出点G在PD上的位置,并加以证明;
(3)求平面PAF与平面PCD夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd893c4964b7f1ef69f0563d74c76d0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21ea52361458ce2e49ed0fe99d8e6c02.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/03bf86d4-be07-4242-89cf-a390e5adc0b0.png?resizew=226)
(1)求证:AD⊥平面PAC;
(2)试在线段PD上确定一点G,使
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
(3)求平面PAF与平面PCD夹角的余弦值.
您最近一年使用:0次
2022-11-22更新
|
328次组卷
|
5卷引用:北京市顺义牛栏山第一中学2020-2021学年高二上学期期中数学试题
名校
解题方法
6 . 将平面直角坐标系中的一列点
.记为
,设
,其中
为与y轴正方向相同的单位向量若对任意的正整数n,都有
,则称
为T点列.
(1)判断点列
是否为T点列,直接写出结果;
(2)求证
是T点列:
(3)若
为T点列,且
.任取其中连续三点
,证明
为钝角三角形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71fa0a4178c2ab8acf3342d228ed8e28.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32f4f7da7655b76971cdf3e11600a9f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/869434cabde100f74953780653d3a2e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88364f251f3d8a14d9784588f45f7acf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e972e658495ad2b603e2b11f3d5e20ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32f4f7da7655b76971cdf3e11600a9f3.png)
(1)判断点列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcf87e7e5ae1e3d45c2ccd73dd8d29a2.png)
(2)求证
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed6ec98836c8c456b45ab94f9aa5a7fb.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32f4f7da7655b76971cdf3e11600a9f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08ed0fe3ab3607bcc987be7ba9ae5bc2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ade2b9aa97d71e08923f71c8eba032a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d24dc108423b4ca4d3b94e9779089f73.png)
您最近一年使用:0次
7 . 对于正整数集合A={a1,a2,…,an}(n∈N*,n≥3),如果去掉其中任意一元素ai(i=1,2,…,n)之后,剩余的所有元素组成的集合都能分为两个交集为空集的集合,且这两个集合的所有元素之和相等,就称集合A为“平衡集”.
(Ⅰ)判断集合Q={1,3,5,7,9}是否是“平衡集”并说明理由;
(Ⅱ)求证:若集合A是“平衡集”,则集合A中元素的奇偶性都相同;
(Ⅲ)证明:四元集合A={a1,a2,a3,a4},其中,a1<a2<a3<a4不可能是“平衡集”.
(Ⅰ)判断集合Q={1,3,5,7,9}是否是“平衡集”并说明理由;
(Ⅱ)求证:若集合A是“平衡集”,则集合A中元素的奇偶性都相同;
(Ⅲ)证明:四元集合A={a1,a2,a3,a4},其中,a1<a2<a3<a4不可能是“平衡集”.
您最近一年使用:0次
2021-10-24更新
|
282次组卷
|
2卷引用:北京市顺义牛栏山第一中学2020-2021学年高二上学期期中数学试题
名校
解题方法
8 . 如图1,已知菱形AECD的对角线AC,DE交于点F,点E为AB的中点.将三角形ADE沿线段DE折起到PDE的位置,如图2所示.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/3/75355912-2ce9-419b-a0fd-5b867b920c65.png?resizew=409)
(1)求证:
;
(2)试问平面PFC与平面PBC所成的二面角是否为
,如果是,请证明;如果不是,请说明理由;
(3)在线段PD,BC上是否分别存在点M,N,使得平面
平面PEN?若存在,请指出点M,N的位置,并证明;若不存在,请说明理由.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/3/75355912-2ce9-419b-a0fd-5b867b920c65.png?resizew=409)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3672e603d06c9186edd20cfc662d8dc.png)
(2)试问平面PFC与平面PBC所成的二面角是否为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
(3)在线段PD,BC上是否分别存在点M,N,使得平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3fe10db2e675faefe668d357ceb0633.png)
您最近一年使用:0次
2020-11-07更新
|
819次组卷
|
4卷引用:北京市顺义区2019-2020学年高一下学期期末质量监测数学试题
北京市顺义区2019-2020学年高一下学期期末质量监测数学试题(已下线)大题专项训练18:立体几何(折叠问题)-2021届高三数学二轮复习北京市汇文中学2020-2021学年高一下学期期末数学试题广东省广州市十六中2021-2022学年高一下学期期中数学试题
名校
9 . 对于正整数集合
,如果任意去掉其中一个元素
之后,剩余的所有元素组成的集合都能分为两个交集为空集的集合,且这两个集合的所有元素之和相等,就称集合
为“可分集合”.
(1)判断集合
和
是否是“可分集合”(不必写过程);
(2)求证:五个元素的集合
一定不是“可分集合”;
(3)若集合
是“可分集合”.
①证明:
为奇数;
②求集合
中元素个数的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a570dbedf552f9d57ec0414e54f3386a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62c4392f75c09edaec2e70c9eccb2b85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(1)判断集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66b07a67307d5d4627efa688b30e5573.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38aa0ba6ea6e8f10a2159defda4e67f8.png)
(2)求证:五个元素的集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1752a1d13ec6a233405fce4d5af61d8f.png)
(3)若集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a570dbedf552f9d57ec0414e54f3386a.png)
①证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
②求集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
您最近一年使用:0次
2019-12-27更新
|
574次组卷
|
4卷引用:北京市顺义区牛栏山第一中学2019-2020学年高三上学期期中数学试题
北京市顺义区牛栏山第一中学2019-2020学年高三上学期期中数学试题北京市密云区2019-2020学年高一上学期期末数学试题(已下线)第1章《集合》 培优测试卷(二)-2021-2022学年高一数学上册同步培优训练系列(苏教版2019)(已下线)专题05 集合与常用逻辑用语压轴题型汇总-2021-2022学年高一《新题速递·数学》(人教A版2019)
10 . 如图,在四棱锥
中,
,底面
为平行四边形,
平面
.
![](https://img.xkw.com/dksih/QBM/2018/3/29/1912173732118528/1912683238678528/STEM/ea6a7864131049a39c5fd6644cca9d4b.png?resizew=193)
(
)求证:
平面
;
(
)若
,
,
,求三棱锥
的体积;
(
)设平面
平面
直线
,试判断
与
的位置关系,并证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65f64a9e1e5fb025d9c3e721150ebc27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec346cba41b378fcd97f1607835e259a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/689c065652544780be8b33ae92cbb6d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://img.xkw.com/dksih/QBM/2018/3/29/1912173732118528/1912683238678528/STEM/ea6a7864131049a39c5fd6644cca9d4b.png?resizew=193)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fb01d2b57580731c8b807ac8cffc8ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de927f7e512ea6302e38ef1b453e58c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ffc3552dd835a9ee6022bb11397a1bd.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64899adb2cc8913ed7d511eade821422.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0342f7bc94dcc0576863e4803413b134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
您最近一年使用:0次
2018-03-29更新
|
458次组卷
|
2卷引用:北京顺义牛栏山一中2017-2018学年高二上期中数学真题卷