如图,在四棱锥
中,
是边长为6的正方形
的中心,
平面
.
![](https://img.xkw.com/dksih/QBM/2022/5/27/2988292849590272/2989128809848832/STEM/a56d38f8-601a-4ec3-b982-e712ee6800b0.png?resizew=186)
(1)求证:平面
平面
;
(2)若
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e126c16032892966489053f44b9048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/2022/5/27/2988292849590272/2989128809848832/STEM/a56d38f8-601a-4ec3-b982-e712ee6800b0.png?resizew=186)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91ce0586aafd9bf4fb7e1be082624afc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b33b7213d99a817bff19bcf740a0697c.png)
更新时间:2022-05-28 14:21:02
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,梯形
中,
,
,平行四边形
的边
垂直于梯形
所在的平面,
,
,
是
的中点,
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/20/c48eb79f-3696-41dc-ab3a-e74fcf3fb77d.png?resizew=181)
(1)求证:平面
平面
;
(2)求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9060f03b9ee41d70d135b1e1a8902ce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de8cc58ef27567f0ab06eb1012aec330.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4e86d02714267ee5a2a8a607dc675ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/20/c48eb79f-3696-41dc-ab3a-e74fcf3fb77d.png?resizew=181)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3547a914468b082d8d8741b974a03190.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02a7ba7cd0c654714c967a900513ba16.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图,图1是由正方形
,直角梯形
组成的一个平面图形,其中
,将正方形
沿
折起,使得
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/acebd3da-c868-4c4d-a09b-904aff4f27e0.png?resizew=231)
(1)求证:平面
平面
;
(2)求平面
与平面
所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0eda685f9d954cd6bea7e0da9e0f6a4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50f218914337edd06e59e75d90b777e6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/acebd3da-c868-4c4d-a09b-904aff4f27e0.png?resizew=231)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d62d30d732c3c6ee3f0dd66d7059356.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fa3254460ecbacecb3e57c5dce227f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a09d9d486b7f91ba933210dd013a7f2c.png)
您最近一年使用:0次
【推荐1】如图,三棱柱
的所有棱长都是2,
平面
,
,
分别是
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/12/2ff0a7e7-a98f-4c2c-b103-e78e64dc26a2.png?resizew=215)
(1)求证:平面
平面
;
(2)求平面
和平面
夹角的余弦值;
(3)在线段
(含端点)上是否存在点
,使点
到平面
的距离为
?若存在,请指出点
的位置,并证明你的结论;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.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/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/12/2ff0a7e7-a98f-4c2c-b103-e78e64dc26a2.png?resizew=215)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/036a0d3b3c70d41060bc441ddd8003fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4da1e02a100d77dff34f8680eba878aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/982a72de174de5de98aa58b4c7d5a886.png)
(3)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1859959fdb4c5edd8056893f94a10a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9868f77d5ab5073b6145f1c6d272122e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
您最近一年使用:0次
解答题
|
适中
(0.65)
名校
【推荐2】如图,已知点
分别是
的边
的中点,连接
,现将
沿
折叠至
的位置,连接
.记平面
与平面
的交线为
,二面角
大小为
.
(1)证明:
平面
;
(2)证明:平面
平面
;
(3)求平面
与平面
所成锐二面角大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dec2ca6438c82b43f746057d8129885.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f460edcced5597615113c0fdc95b1dfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f07107087ce4abdfa5fc68fe6fb62f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/390f612b4fb72c68c2235a06efec140b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9afac7c616bbb14e1ed428a3c507c7dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/657dffbd3623b705f871878fbd9df57e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdf257663b954b4a9e4fe1edef662c9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d867c6797f6187d4ad533851fe6f397.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23976db53f05b3d5d791c4d736a7184d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65c42bce098904b241986bb91c65ab33.png)
(2)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21dee56b9f36ba8f76fe67b76383636b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a98287a302228ece1fa53c5c66c590f.png)
(3)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9afac7c616bbb14e1ed428a3c507c7dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/657dffbd3623b705f871878fbd9df57e.png)
![](https://img.xkw.com/dksih/QBM/2018/2/3/1874542947426304/1875252161904640/STEM/74ebb5c3b7d8403eb7e46787c6db72ec.png?resizew=345)
您最近一年使用:0次