解题方法
1 . 如图,已知三棱锥
的三条侧棱
,
,
两两垂直,且
,
,
,三棱锥
的外接球半径
.
(1)求三棱锥
的侧面积
的最大值;
(2)若在底面
上,有一个小球由顶点
处开始随机沿底边自由滚动,每次滚动一条底边,滚向顶点
的概率为
,滚向顶点
的概率为
;当球在顶点
处时,滚向顶点
的概率为
,滚向顶点
的概率为
;当球在顶点
处时,滚向顶点
的概率为
,滚向顶点
的概率为
.若小球滚动3次,记球滚到顶点
处的次数为
,求数学期望
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00803e67a5d417a9a4dc00277fca778b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/495636df02b96acab4478baabe77bafa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69acd73890957b0007b30fd81f2abc0e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e159fa38488741d395ea9cb03386b1ad.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/18/58b499d6-5736-43f6-94b9-dd6be5e9ef67.png?resizew=139)
(1)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
(2)若在底面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bf3baba074e8aeb6f3ea117865bbd1b.png)
您最近一年使用:0次
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2 . 如图,长方体
中,AB=AD=2,A
=4,P为棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/16/88d83e9e-1b69-4227-aef8-56917085b107.png?resizew=127)
(1)求直线
与平面
所成角的余弦值;
(2)求直线AP被长方体
的外接球截得的线段长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/16/88d83e9e-1b69-4227-aef8-56917085b107.png?resizew=127)
(1)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)求直线AP被长方体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
您最近一年使用:0次
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3 . 如图,四棱锥
中,四边形
为矩形,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/74475663-c355-455d-bbf0-c3f374a53c06.png?resizew=183)
(1)求证:
平面
;
(2)求四棱锥
外接球的体积.
![](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/080ca48cd27d4bf9d9ef084b558fc17a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da426f62147ca7fb8d3314ca9dffbeb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9971233dc3e8ef828046fbb94101b9d0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/74475663-c355-455d-bbf0-c3f374a53c06.png?resizew=183)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6deecf9ccb7b7879455050633219e09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d923a338dd2d2e29336b42574d38448.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
您最近一年使用:0次
2020-07-23更新
|
380次组卷
|
2卷引用:河北省保定市2019-2020学年高一下学期期末数学试题
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4 . 如图所示,如果一个几何体的正视图与侧视图是全等的长方形,且边长分别是4与2,俯视图是一个边长为4的正方形
![](https://img.xkw.com/dksih/QBM/2019/1/14/2118643610148864/2119868467372032/STEM/973b0031647a43a491e45dfba9334f47.png?resizew=271)
(Ⅰ)求该几何体的表面积;
(Ⅱ)求该几何体的外接球的体积
![](https://img.xkw.com/dksih/QBM/2019/1/14/2118643610148864/2119868467372032/STEM/973b0031647a43a491e45dfba9334f47.png?resizew=271)
(Ⅰ)求该几何体的表面积;
(Ⅱ)求该几何体的外接球的体积
您最近一年使用:0次
2018-08-03更新
|
439次组卷
|
2卷引用:【全国市级联考】河北省张家口市2017-2018学年高一下学期期末考试数学试题