如图,四边形
是菱形,
,平面
平面
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2022/4/26/2966410405871616/2997572027817984/STEM/fd59fe59-53b1-4e93-a6bc-9a021fcb4ae7.png?resizew=156)
(1)证明:平面
平面
;
(2)在棱
上是否存在点
使得平面
与平面
所成的锐二面角的余弦值为
,若存在,求
的值,若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c161375e4e6f61f1cbef8083c02e975.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3abb27f8d654064a92f9d7a11e586ab5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00566b498fa4a541e154ffcf2c19d0fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f817dfa5aaaf4795e69ef1eb86e291fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9db203a75be4335050febf55bc53d596.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4280be91682e5d8a0d0704190319bb.png)
![](https://img.xkw.com/dksih/QBM/2022/4/26/2966410405871616/2997572027817984/STEM/fd59fe59-53b1-4e93-a6bc-9a021fcb4ae7.png?resizew=156)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/677d1863ff4d8ac1604b18149d4f320f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a681d311a864d38cf306a0c137cbcca.png)
(2)在棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9af29254fe60a392c249c5791279e9c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4734735213b599a9915e1ed91a5d8ce4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6328d3555c993eafea4401032ceb807.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/180d6f93806a6d4b6c19cf35b48eec0c.png)
更新时间:2022-06-09 12:38:48
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图所示,在多面体
中,四边形
是正方形,
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/2018/2/10/1879305641287680/1880177770356736/STEM/bfada2fbc0584469a4bbcc49f8c72276.png?resizew=152)
(1)求证:
平面
;
(2)求证:平面
平面
.
![](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/14d184d748ba2cd3c472015826393caa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89a096dfcaaee18f1cd13f206720a78.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/2018/2/10/1879305641287680/1880177770356736/STEM/bfada2fbc0584469a4bbcc49f8c72276.png?resizew=152)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38f7dd424c1184e0656dcdad0e8b6d84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3547a914468b082d8d8741b974a03190.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4734735213b599a9915e1ed91a5d8ce4.png)
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解题方法
【推荐2】如图所示,在高为2的三棱锥
中(
为底面),
,
为
的中点.若三棱锥
的体积为
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/1/7064645e-0e6f-4df8-9e0b-57e2b9686906.png?resizew=153)
(1)证明:平面
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76389a24c2b7c65baa31830ddd5bd2d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98468aa32f43517ed67e164c63d8dec9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d599cb4a589f90b0205f24c2e1fa021e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/1/7064645e-0e6f-4df8-9e0b-57e2b9686906.png?resizew=153)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3d7090639341730951c1bc3c9b6164e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a438393ddfc7da1804baf4932442bb35.png)
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解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】在四棱锥
中,底面
为菱形,
和
为正三角形,
为
的中点.
(1)证明:
平面
.
(2)若
,求平面
与平面
夹角的余弦值.
![](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/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acee03d4bb4667b6c345221b6c9b0fa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/30/bb047197-c667-4351-accb-9d29defe1291.png?resizew=185)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8c2b786c64e6a9ed2ec5670cde74f86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0277aa467e74986cc5c31b975eb5f7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
您最近一年使用:0次
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适中
(0.65)
解题方法
【推荐2】如图,在四棱锥P-ABCD中,平面PAB⊥平面ABCD,PA=PB,AD∥BC,AB=AC,AD=
BC=1,PD=3,∠BAD=120°,M为PC的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/2344f317-f823-4e04-b0dc-c1e823ca359b.png?resizew=192)
(1)证明:DM∥平面PAB;
(2)求四面体MABD的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/2344f317-f823-4e04-b0dc-c1e823ca359b.png?resizew=192)
(1)证明:DM∥平面PAB;
(2)求四面体MABD的体积.
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
名校
解题方法
【推荐1】如图,三棱锥P-ABC中,
平面ABC,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/24/5161beed-3ce3-4b4f-95dd-bfdb26f74cc1.png?resizew=232)
(1)求三棱锥A-PBC的体积;
(2)在线段PC上是否存在一点M,使得
?若存在,求
的值,若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcc532cfe64300cb3da9e04a307c957a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb5b12692517a39c320f99a479eb055.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b57fdd2a3642716fcf5100011eb3ec88.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/24/5161beed-3ce3-4b4f-95dd-bfdb26f74cc1.png?resizew=232)
(1)求三棱锥A-PBC的体积;
(2)在线段PC上是否存在一点M,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d3f843b83e62bab294988a7ea134a63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/553e63fd37dc70bb89410d685adfd5d8.png)
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【推荐2】在如图所示的几何体中,四边形
为正方形,四边形
为直角梯形,且
,
,平面
平面
,
.
![](https://img.xkw.com/dksih/QBM/2018/12/6/2091082894270464/2094386761940992/STEM/eb9859cf89624d1d81f4d9c12644b0d6.png?resizew=170)
(1)求证:
平面
.
(2)若二面角
为直二面角,
(ⅰ)求直线
与平面
所成角的大小.
(ⅱ)棱
上是否存在点
,使得
平面
?若存在,求出
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e64f1d9d1dfa1cb58eba4218745373a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf4dc4d7d30af1cdce660795e0fd7d7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45ec097d894a854d83946648f8b5fee9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b05b05f4f031889c7f5c0e1750804c9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3e1d5146233a1c02370bea48615429b.png)
![](https://img.xkw.com/dksih/QBM/2018/12/6/2091082894270464/2094386761940992/STEM/eb9859cf89624d1d81f4d9c12644b0d6.png?resizew=170)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/315052802c3c31d78d894cda26204224.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d87b527147cb8dbb475bcefc0da2e6d.png)
(ⅰ)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10fc7991ea17d54ff5f4445ac5699463.png)
(ⅱ)棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2b4e753ef119608188c46a50ec597e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ffaec9caabd719bf8c1fcdde117ea5d.png)
您最近一年使用:0次