1 . 如图1所示,在矩形
中,
,
为
的中点,沿
将
折起,如图2所示,在图2中,
分别为
的中点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/30/1f04f406-c7e0-4835-b848-7c66cf866922.png?resizew=332)
(1)求证:面
面
;
(2)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abc28e69c1ba0aac981256887f7dfa94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ccbf98ff1b1f121ee3aa3dec108ba0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb523887cb434b768939b1853ed234d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3707df06fec3476c1b635e7083b5cc35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58ef478c804c71ad3b374196a8ca9d74.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/30/1f04f406-c7e0-4835-b848-7c66cf866922.png?resizew=332)
(1)求证:面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d28c625d7ac6878957facc8274d459c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01ff27eea7545bb06f9472f91290c54e.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb0d53391ba78421bf1cfe3bec4782bc.png)
您最近一年使用:0次
2 . 如图,在四棱锥
中,底而
为正方形,
底面
,
,点
为棱
的中点,点
,
分别为棱
,
上的动点(
,
与所在棱的端点不重合),且满足
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/fddf669c-b9eb-4921-8fa0-23e058d01f08.png?resizew=178)
(1)证明:平面
平面
;
(2)当三棱锥
的体积最大时,求二面角
的余弦值
![](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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f83a04565a8ebaa111894b724b0ba266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d96a5d40d0aea9f4398ca4d0fe9b0dd.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/fddf669c-b9eb-4921-8fa0-23e058d01f08.png?resizew=178)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f020ca4ad44801691235958e253907d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9af29254fe60a392c249c5791279e9c8.png)
(2)当三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43bc3723fc611b3789b899d8817fc514.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93b0abafcdb0e9435a17c0d80790afaa.png)
您最近一年使用:0次
2019-04-04更新
|
661次组卷
|
2卷引用:【市级联考】山东省济南市2019届高三3月模拟考试理科数学试题
3 . 如图(1)是一个水平放置的正三棱柱
,是棱
的中点.正三棱柱的主视图如图(2).
![](https://img.xkw.com/dksih/QBM/2012/4/22/1570838867165184/1570838872776704/STEM/041e804306cd440ca5bf25ab27dc327c.png?resizew=506)
(Ⅰ) 图(1)中垂直于平面
的平面有哪几个?(直接写出符合要求的平面即可,不必说明或证明)
(Ⅱ)求正三棱柱
的体积;
(Ⅲ)证明:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5ffe04639a4f1c0b24510edc9f41f3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/2012/4/22/1570838867165184/1570838872776704/STEM/041e804306cd440ca5bf25ab27dc327c.png?resizew=506)
(Ⅰ) 图(1)中垂直于平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
(Ⅱ)求正三棱柱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
(Ⅲ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3eb298c094438b58734a152e0f9d7b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ace4ac6d80ef00952266d165a77a4630.png)
您最近一年使用:0次
4 . 如图,在三棱锥
中,
底面
,点
,
分别在棱
上,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/14/57fcf6fd-7399-4ae0-96e5-11f792a852e8.png?resizew=157)
(Ⅰ)求证:
平面
;
(Ⅱ)当
为
的中点时,求
与平面
所成的角的大小;
(Ⅲ)是否存在点
使得二面角
为直二面角?并说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf87a9d568ef3935c603efcfee863126.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589c3cc1f331dbb2248b0829039df7f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95a078495ba47076ccaa28b46f765d80.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/14/57fcf6fd-7399-4ae0-96e5-11f792a852e8.png?resizew=157)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(Ⅱ)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(Ⅲ)是否存在点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ed479427d768bbf98c15141589109e1.png)
您最近一年使用:0次
2016-11-30更新
|
1832次组卷
|
6卷引用:2013届山东省淄川一中高三12月月考理科数学试卷
(已下线)2013届山东省淄川一中高三12月月考理科数学试卷2009年普通高等学校招生全国统一考试理科数学(北京卷)(已下线)2010年大连市第三十六中学高三高考压轴考试理科数学卷(已下线)2010-2011年重庆市完胜田家炳中学高二下学期检测数学试卷(已下线)2012届湖北省岳口中学高三模拟考试理科数学试卷二【市级联考】安徽省定远重点中学2018-2019学年高二上学期第三次月考数学(理)试题