如图,在四棱锥
中,底面
是边长为2的菱形,
,
,且平面
平面
.
![](https://img.xkw.com/dksih/QBM/2022/5/17/2981467014750208/2982704202211328/STEM/c866f5d7-1d48-40aa-a887-7dd18526b217.png?resizew=162)
(1)证明:平面
平面
;
(2)若Q为棱
上一点,且
,求二面角
的大小.
![](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/1bae7599ad243c12d94325ad917f0a44.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3755b2bcf7516eedb26a27ad73657216.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/2022/5/17/2981467014750208/2982704202211328/STEM/c866f5d7-1d48-40aa-a887-7dd18526b217.png?resizew=162)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)若Q为棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4fc0b2955d06fbb4e5f2dd047c253f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84ea10539215794cd76e8b211abd503f.png)
更新时间:2022-05-19 12:30:08
|
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】如图,多面体
中,
,
平面
,四边形
是菱形.
![](https://img.xkw.com/dksih/QBM/2018/5/31/1957148377391104/1961568540639232/STEM/2bdb0edb41f94a40a2502a58d3d1083d.png?resizew=207)
(1)证明:平面
平面
;
(2)若
,
,设
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f406a4d855d9f492d392b6c31e8fd26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67922f83ef857cf60fe61871cee79f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44b190c8d3d7d7d0e6e959e8a52eae90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
![](https://img.xkw.com/dksih/QBM/2018/5/31/1957148377391104/1961568540639232/STEM/2bdb0edb41f94a40a2502a58d3d1083d.png?resizew=207)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4a46fbde58e12b1edc038ae9e921722.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a09d9d486b7f91ba933210dd013a7f2c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4cfd870858f2c9bb6e89c2f41b5d653.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99bfbda63659d71acd2a4c950ba20692.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/596be055fc960a28d01f32366c2b9490.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7ddd5db68b947a125e6fd226c568d56.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐2】如图所示,在平行四边形
中,
,
,
,点
是
边的中点,将
沿
折起,使点
到达点
的位置,且
.
![](https://img.xkw.com/dksih/QBM/2019/4/18/2185129764995072/2185297104101376/STEM/ed8eb8f4d8a24ded840429ee950001e0.png?resizew=161)
(1)求证:平面
平面
;
(2)若平面
和平面
的交线为
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c1ac2e11788860424508ea9e80cf89d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c42ed2e5bd5a0f033e24008697bf4963.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/38efab2b954882d5d6b664b2a8d4c879.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e99998f33ad6edab18180627d4903dcc.png)
![](https://img.xkw.com/dksih/QBM/2019/4/18/2185129764995072/2185297104101376/STEM/ed8eb8f4d8a24ded840429ee950001e0.png?resizew=161)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90d96357a07048ba79b8c84097d359d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01ff27eea7545bb06f9472f91290c54e.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e6c2dad46a9052a4185a4f7b4ae8a2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3b91a7e09cc36dbd8cf4a625e270898.png)
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解答题-问答题
|
适中
(0.65)
【推荐1】如图,平面
是
的一条斜线,
是
在平面
内的射影,
为斜线和平面所成的角.设
,过
作
的垂线
,连结
,则
,且
即为二面角
的平面角(锐二面角),设
.
请推导关于的等式关系(1);关于
的等式关系(2).并用上述两结论求解下题:
设和
所在的两个平面互相垂直,且
,求二面角
的正弦值的大小.
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图,正方形
所在平面与四边形
所在平面互相重直,
是等腰直角三角形,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/8f09883b-5d4a-46bf-9c77-43ceaf21ce6d.png?resizew=198)
(1)求证:
平面
;
(2)设线段
、
的中点分别为
、
,求
与
所成角的正弦值;
(3)求二面角
的平面角的正切值.
![](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/cc3814287dbb60d478bffc5366f9928b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48a277db452e76240ec83ec6a2864bdd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af8bfe298fb2948547723517cd2ec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef2593f2e4c6c7677bc1180660a43801.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/8f09883b-5d4a-46bf-9c77-43ceaf21ce6d.png?resizew=198)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a5f445af1ae136773cb338920552ff2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
(2)设线段
![](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/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9b123303738a595ec0126beb0fa64a8.png)
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解答题-问答题
|
适中
(0.65)
【推荐3】如图,在四棱锥
中,底面
满足
平面
,且
.
![](https://img.xkw.com/dksih/QBM/2021/12/14/2872422041985024/2948680346017792/STEM/5e8825be67364788b6fbf7f7629eb568.png?resizew=184)
(1)证明:
平面
;
(2)求平面
与平面
夹角的余弦值.
![](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/4d101cd311efd7e9cf066eb7a4136313.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2adb8e53cd26c16216a001eeb84dc7e7.png)
![](https://img.xkw.com/dksih/QBM/2021/12/14/2872422041985024/2948680346017792/STEM/5e8825be67364788b6fbf7f7629eb568.png?resizew=184)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc9c9cfa597b444b5c9dbae7a825a695.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d923a338dd2d2e29336b42574d38448.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21665d21bbfb04410c78345de1fd15ae.png)
您最近一年使用:0次