名校
1 . 三棱锥
中,
,
分别为
,
中点,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/14/82f4eb9c-2133-431f-8f0c-c507476eb415.png?resizew=218)
(1)求证:
平面
;
(2)求异面直线
与
所成角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6559aabe16c2318687089e7cc498b98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a65d5853c26657db448af610ac72cca4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/14/82f4eb9c-2133-431f-8f0c-c507476eb415.png?resizew=218)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ce03b310edce42191f9fa75a1c909ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
您最近一年使用:0次
2023-02-13更新
|
414次组卷
|
3卷引用:上海市向东中学2022-2023学年高二上学期期末数学试题
名校
2 . 在
中,设
,
,求证:
的面积
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9b36392ec1e9dbab87d66059be35ed3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e8f1336ac2ff3658955b807eb0a27a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f555d99ad85ba7d630648a297855fbbc.png)
您最近一年使用:0次
3 . 如图,在四棱锥
中,底面
为等腰梯形,
,
,
平面
,
,点
为线段
中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/1/a9f935db-30a7-4ee1-b8c9-ef0bdf23f907.png?resizew=156)
(1)求证:
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6e0b64d25ddd18454f88e40c45d7d8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c83f8945042b9c8fb2fbdac9308d62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39c049bbf873a6af116712840484b98f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/defa5b53043ae802bb1af7d14374406d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/1/a9f935db-30a7-4ee1-b8c9-ef0bdf23f907.png?resizew=156)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5928c98b341b16d4b5a5b931d2929d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc9c9cfa597b444b5c9dbae7a825a695.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/735056c174e8dd7906257a2a50a962a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5000fea066102e62cf2128ccbbd2b3e3.png)
您最近一年使用:0次
2023-07-31更新
|
551次组卷
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2卷引用:福建省福州市福清港头中学2022-2023学年高二下学期期末质量检查数学试题
23-24高二上·上海·课后作业
4 . 如图,在三棱锥
中,
,
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d301216769d4e56cd744c9bfeb1fedb.png)
(1)求
,并说明异面直线
与
所成角
的大小在棱
长度增大时是怎样变化的.
(2)判断点
在平面
上的射影是否可能在直线
上?说出你的结论并加以证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4357d5744046d4d44abb09e1ee35fcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fce9920af1cb3802b6d095e4ffa94142.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca036d049f5205cf04cb1b9c5cd03f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d301216769d4e56cd744c9bfeb1fedb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/16/2171d2b7-069e-4c21-9201-e14751e793ab.png?resizew=145)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3b3dff6522c24a955ea87891d2a7b25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
(2)判断点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
您最近一年使用:0次
名校
5 . 公元263年,刘徽首创了用圆的内接正多边形的面积来逼近圆面积的方法,算得
值为3.14,我国称这种方法为割圆术,直到1200年后,西方人才找到了类似的方法,后人为纪念刘徽的贡献,将3.14称为徽率.我们作单位圆的外切和内接正
边形
,记外切正
边形周长的一半为
,内接正
边形周长的一半为
.通过计算容易得到:
(其中
是正
边形的一条边所对圆心角的一半)
(1)求
的通项公式;
(2)求证:对于任意正整数
依次成等差数列;
(3)试问对任意正整数
是否能构成等比数列?说明你的理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbbc0cf9164007ddd298dd2236703f2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bbccb799ae7eb992b25b2426173ed36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbbc0cf9164007ddd298dd2236703f2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbbc0cf9164007ddd298dd2236703f2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/686ece75006ad358f23314dc8a246e11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96936fc2a366e6a8d1dfae54322d5d4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92ffa8be5a02790c6161c56b8e90db64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbbc0cf9164007ddd298dd2236703f2f.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)求证:对于任意正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ac64c640ccd57708681eada27a8fa6d.png)
(3)试问对任意正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8e42bf4d8449d427c1f5f252db0f298.png)
您最近一年使用:0次
2023-07-21更新
|
386次组卷
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3卷引用:4.3.1 等比数列的概念——课后作业(提升版)
名校
解题方法
6 . 已知
的内解
所对的边分别为
,满足
.
(1)求证:
;
(2)若
为
上一点,且
,求
的面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1db789b3e162dc967f1fb1dc58a988fa.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baa8d75a6638e08eedbff8662267da6f.png)
(2)若
![](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/df01d40611ad128b314244ac8090cd95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
您最近一年使用:0次
2023-07-16更新
|
581次组卷
|
2卷引用:广东省汕头市金山中学2023-2024学年高二上学期10月阶段考试数学试卷
7 . 已知在
中,D是BC边上一点.
(1)若
,
,
,求证:
;
(2)若
,
,
,
,BC边的长大于4,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4376af85e07b29051a812ff3fcda61a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a70c01e50e1f515598300f18278324a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4b85155ef02a3d4ad84819e14d0c12a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ead64391e42f81943e500aed314e4b4.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55493e331f88d3d1c396e92b46c97ecd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16e0c5cb53fd85b7a23f0580df6bb49a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4fc2d383876afe5be1103352571805b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfb08f6a798dc293f3d8de281190f65e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
您最近一年使用:0次
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解题方法
8 . 已知直三棱柱
中,侧面
为正方形,
,E,F分别为AC和
的中点,D为棱
上的动点.
.
(1)证明:
;
(2)求平面
与平面DEF所成的二面角正弦值的最小值及此时点D的位置.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9edc50f7febbc2d5d8dcdc23a3630a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3570a95f68349fcd9417fcda62e78e7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0023280949eda97787964f0a9d41ed2e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/3/d14dff13-2f48-4595-a507-c9ae701b1f2a.png?resizew=129)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a7a3dc3f3a02f4400e22dec2f2fee23.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc6184b191e6da43911e701121517e.png)
您最近一年使用:0次
2023-05-31更新
|
457次组卷
|
4卷引用:第09讲 拓展三:二面角的传统法与向量法(含探索性问题,7类热点题型讲练)-【帮课堂】2023-2024学年高二数学同步学与练(人教A版2019选择性必修第一册)
(已下线)第09讲 拓展三:二面角的传统法与向量法(含探索性问题,7类热点题型讲练)-【帮课堂】2023-2024学年高二数学同步学与练(人教A版2019选择性必修第一册)(已下线)第06讲 1.4.2用空间向量研究距离、夹角问题(2)(已下线)专题09 空间向量中动点的设法2种常见考法归类 - 【考点通关】2023-2024学年高二数学高频考点与解题策略(人教A版2019选择性必修第一册)黑龙江省哈尔滨市第六中学校2023届高三第三次模拟考试数学试题
名校
解题方法
9 . (1)已知
,
,求
的值;
(2)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9b6a343f3c99fdb49698d98e2e60bf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0608f6bdf1ab77c08376224a2a8aef87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d66c03d4ca06819a6ce7fc8ea6de0f0.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/102e424efac9769c087b25c1d1acb185.png)
您最近一年使用:0次
名校
10 . 如图,已知四面体
中,
平面
,
.
![](https://img.xkw.com/dksih/QBM/2023/1/11/3150440558288896/3150756208951296/STEM/341340cd0e2846c889c35ee695ee889d.png?resizew=181)
(1)求证:
;
(2)《九章算术》中将四个面都是直角三角形的四面体称为“鳖臑”,若此“鳖臑”中,
,有一根彩带经过面
与面
,且彩带的两个端点分别固定在点
和点
处,求彩带的最小长度;
(3)若在此四面体中任取两条棱,记它们互相垂直的概率为
;任取两个面,记它们互相垂直的概率为
;任取一个面和不在此面上的一条棱,记它们互相垂直的概率为
. 试比较概率
、
、
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bd6a2b112facda441f4e34bf5c145fa.png)
![](https://img.xkw.com/dksih/QBM/2023/1/11/3150440558288896/3150756208951296/STEM/341340cd0e2846c889c35ee695ee889d.png?resizew=181)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf10d92f20501e19d25f6f4159aab89.png)
(2)《九章算术》中将四个面都是直角三角形的四面体称为“鳖臑”,若此“鳖臑”中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce519312a849963b376c202c3f9d7cf7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
(3)若在此四面体中任取两条棱,记它们互相垂直的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
您最近一年使用:0次
2023-01-11更新
|
389次组卷
|
3卷引用:上海市浦东新区2022-2023学年高二上学期期末数学试题