已知五面体
中,四边形
为矩形.
![](https://img.xkw.com/dksih/QBM/2020/8/23/2534261553512448/2542432970964992/STEM/3d7768ff89c248cd9855d5c3fa13639c.png?resizew=201)
(1)证明:
平面
;
(2)若
,求证:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://img.xkw.com/dksih/QBM/2020/8/23/2534261553512448/2542432970964992/STEM/3d7768ff89c248cd9855d5c3fa13639c.png?resizew=201)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/307807ee10071bafbe922eb18d2517d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a0e5697eca3f5205cb7b343648240bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d28c625d7ac6878957facc8274d459c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
更新时间:2020-09-04 11:36:01
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图所示,在三棱柱
中,底面
是正三角形,侧面
是菱形,点
在平面
的射影为线段
的中点
,过点
,
,
的平面
与棱
交于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/18/9c2d92c5-10de-4801-95c1-2e55401297ea.png?resizew=177)
(1)证明:四边形
是矩形;
(2)求平面
和平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8ba846c4dec057a9eec4174306efd06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/18/9c2d92c5-10de-4801-95c1-2e55401297ea.png?resizew=177)
(1)证明:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/202794c51b2166eca170da9c53247bea.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd06851d747f8ccf046bc807b2523e65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6668c79fb70d1fef682cdf629a851ed.png)
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【推荐2】如图,三棱台
中,侧面
与侧面
是全等的梯形,若
,且
.
![](https://img.xkw.com/dksih/QBM/2020/2/21/2404057610870784/2404718270889984/STEM/901cc338-a628-4d05-9fd3-1058895b2f27.png)
(1)若
与
交于点
在线段
上且满足
,证明:
平面
;
(2)若二面角
为
,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bea124cef7ab3fd8069243e9894d1c59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72f0d0e78101fef36a75b70ac7e7cf5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d574d643ef26eabe955d73c2a7fca52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00372f6d171446605e084c57bb5d2142.png)
![](https://img.xkw.com/dksih/QBM/2020/2/21/2404057610870784/2404718270889984/STEM/901cc338-a628-4d05-9fd3-1058895b2f27.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a02c25b95e61557eec096de150ab873f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c91f017794d7b675a4cef2a357339bc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d88591679796c52024d11c4de641bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
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解答题-证明题
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适中
(0.65)
名校
解题方法
【推荐1】如图,在四棱锥
中,四边形
为正方形,已知
平面
,且
,
为
中点.
平面
;
(2)证明:平面
平面
.
![](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/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba4c15fb8fc3239d45bd4e7d8971f58e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8c2b786c64e6a9ed2ec5670cde74f86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/342d452a7b850cd3a15b23619ad39bd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
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【推荐2】如图,已知四棱锥P-ABCD的底面为直角梯形,AB∥DC,∠DAB=90°,PA⊥底面ABCD,且PA=AD=DC=1,AB=2,M是PB的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/5/0c05c55d-7aff-4376-b647-e5ffaf419d8e.png?resizew=166)
(1)证明:平面PAD⊥平面PCD;
(2)求AC与PB的夹角的余弦值;
(3)求二面角A-MC-B的余弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/5/0c05c55d-7aff-4376-b647-e5ffaf419d8e.png?resizew=166)
(1)证明:平面PAD⊥平面PCD;
(2)求AC与PB的夹角的余弦值;
(3)求二面角A-MC-B的余弦值.
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解答题-证明题
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适中
(0.65)
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【推荐3】如图1,在边长为4的等边中,
,
分别是
,
的中点.将
沿
折至
(如图2),使得
.
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ac48b9ac8efbf41d6ab5242d247bd89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5c62f22d7afc5627fcb86599faa8e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b37793a3a810e823e10c340986f55ddd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5c62f22d7afc5627fcb86599faa8e1.png)
您最近一年使用:0次