1 . 如图,在长方体
中,底面ABCD是边长为2的正方形,
.
求证:
;
求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd694ad3a4733c7c84aaa7946aeea4de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71fc30662734ee770e2bd433836d90ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4141b26d2c32655003494a91ad6331b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30919ab9ad1b3efecae6b99cc0392440.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65863c1abad833b79c303bfca24f535c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d768c8f969bb0c35b40a8268b797ddb.png)
![](https://img.xkw.com/dksih/QBM/2018/12/7/2091540642529280/2092631607476224/STEM/40d90b91b01348d48449a5564688b90b.png?resizew=214)
您最近一年使用:0次
2018-12-08更新
|
359次组卷
|
2卷引用:【校级联考】重庆市南川三校联考2018-2019学年高二(上)期中数学(理科)试题
2 . 如图所示,在矩形ABCD中,
,
沿对角线将
折起,使点C移到
点,且C点在平面ABD的射影O恰在AB上.
求直线AB与平面
D所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f26a348ffa43e281b57806df029eb271.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/973c73335c9cf139b2f2a8940f0aa06b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b506b0941433a6a5d5387d0ec95596ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f015ed8e497b4394053ddd19683a98f.png)
(1)求证:平面ACD;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65863c1abad833b79c303bfca24f535c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://img.xkw.com/dksih/QBM/2018/12/7/2091540642529280/2092631607492608/STEM/622f156cd53f47afa1d7c3e01928043b.png?resizew=216)
您最近一年使用:0次
18-19高一·全国·单元测试
3 . 如图所示,在矩形ABCD中,AB=3
,BC=3,沿对角线BD将△BCD折起,使点C移到C′点,且C′点在平面ABD上的射影O恰在AB上.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/4/2608b9b9-e4bf-43ef-88a2-bcfdd5e98b38.png?resizew=226)
(1)求证:BC′⊥平面AC′D;
(2)求点A到平面BC′D的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/4/2608b9b9-e4bf-43ef-88a2-bcfdd5e98b38.png?resizew=226)
(1)求证:BC′⊥平面AC′D;
(2)求点A到平面BC′D的距离.
您最近一年使用:0次
解题方法
4 . 如图所示,四棱锥
中,底面
是个边长为
正方形,侧棱
底面
,且
,
是
的中点
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/2/a6fae0a4-4bc0-40eb-9b40-d84bddc5e4f3.png?resizew=170)
(1)证明:
平面
;
(2)求三棱锥
的体积.
![](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/61128ab996360a038e6e64d82fcba004.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/0b80ee363635d73f601654339028daec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/2/a6fae0a4-4bc0-40eb-9b40-d84bddc5e4f3.png?resizew=170)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5928c98b341b16d4b5a5b931d2929d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/965a4fef0f3ffd7c7e6a0d5aef779071.png)
您最近一年使用:0次