如图,在平行六面体
中底面
是边长为
的菱形,
,
为
的中点,
为
上一点,
平面
,
.
![](https://img.xkw.com/dksih/QBM/2021/6/5/2736615037394944/2803263199297536/STEM/7d0879f4-1678-4340-903c-795feba051d5.png?resizew=257)
(I)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c02ffbf0d9a3a73b896732082710c2f.png)
(II)若
,
,①求证:该平行六面体为直四棱柱;②求二面角
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e075468e7fb0bf30229aec01a7205977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f306ff6d237cd9d847aa109acf9333d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70db40c42655327adee01caedfc9d50c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc55d282b5786fc0ac1fcf7e706e3a1.png)
![](https://img.xkw.com/dksih/QBM/2021/6/5/2736615037394944/2803263199297536/STEM/7d0879f4-1678-4340-903c-795feba051d5.png?resizew=257)
(I)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c02ffbf0d9a3a73b896732082710c2f.png)
(II)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55a2310cbba5e050488cd9296eb195d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46e5c289b8aabdbfba95c7fd1e1842f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05d2c1b3fd7524383736c72f4c0f1f27.png)
更新时间:2021-09-07 23:56:29
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,在四棱锥
中,
平面
平分
且与
交于点
为
的中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/5/aa35377b-070e-4540-ab15-9fc3f9952933.png?resizew=148)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
平面
;
(2)若
,求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a154989a035e1dd9fe8301b15c6793e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3981e7286d41960daf4e110c1c84e03a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b92dbe7d01d47d6c2db1396180caf76d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b603ba4fb3db26020749241024f93e85.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/5/aa35377b-070e-4540-ab15-9fc3f9952933.png?resizew=148)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/deb3d0e2134c94753441986f2d0dd753.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c753cb1eb73fd8d136d00462970797.png)
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(0.65)
【推荐2】如图所示,四棱锥
的底面
是直角梯形,
,
,
,
底面
,过
的平面交
于
,交
于
(
与
不重合).
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/6/1c8dffd7-e0c3-4485-944c-b58860d3de1b.png?resizew=227)
(Ⅰ)求证:
;
(Ⅱ)如果
,求此时
的值.
![](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/d5acb763021bf166ca719d07223591d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcabfbc4cf61ef0024bdc48a8d012dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/6/1c8dffd7-e0c3-4485-944c-b58860d3de1b.png?resizew=227)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e987ef5b2677d3b860a9882770ac718.png)
(Ⅱ)如果
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d3f843b83e62bab294988a7ea134a63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47548785e478bc5b9591341a881e3127.png)
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【推荐1】如图,在正方体
中
为
的中点.
(1)求三棱锥
的体积;
(2)若
为
的中点,求证:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bafa7168302e524813426a0fa494c86f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/29/fb0fec78-2c4e-448f-a6d1-a8edc311c0d4.png?resizew=158)
(1)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5d90f940f5693b22ddf2e7c761887d8.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/920f9a182ba419efef8fb4a791c60fee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ef06a52945f8a26a4df410a777d79b7.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,在四棱锥
中,底面ABCD是矩形,侧棱
底面ABCD,E、F、G分别为VA、VB、BC的中点.
![](https://img.xkw.com/dksih/QBM/2021/5/18/2723964203532288/2784037363843072/STEM/03be655f041e4208971a46020a1ac480.png?resizew=168)
(1)求证:平面
平面VCD;
(2)当二面角
、
分别为
、
时,求直线VB与平面EFG所成的角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebfcf34539673d516eb9b259951a81ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9c439e4e4e48b17e19e666d892216fe.png)
![](https://img.xkw.com/dksih/QBM/2021/5/18/2723964203532288/2784037363843072/STEM/03be655f041e4208971a46020a1ac480.png?resizew=168)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1fd975b889bfe7ddcec0de56b6f23ee.png)
(2)当二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4934904f8d01862f3c444f0c39a3827.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a09d63c718c92d3951a6fb1a824e068.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79a97bb4dcfab4ec7539bc783d563c49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6b86c22b670a8e9f3896f9e8883fbbb.png)
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解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】已知
是圆
的直径,且长为4,
是圆
上异于
的一点,点
到
的距离均为
,设二面角
与二面角
的大小分别为
.
(1)求
的值;
(2)若
,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38387ba1cadfd3dfc4dea4ca9f613cea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf29d07c3751c41ab3503065a5a5052e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b796bbaeb8450404c2d146283562006e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4e288596fa3811dd2c17bded60e82e7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/4/bda85095-5689-4f13-8cec-45cd36ad472e.png?resizew=184)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5458c30dbb22889ed27b78ae92f89e78.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf76792693c3d26302f7631276f14398.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a438393ddfc7da1804baf4932442bb35.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐2】在四棱锥
中,
平面
,底面
为正方形,
,E和F分别为
和
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/3/97e305e8-d789-4b54-a36b-cb69e8b2f3c5.png?resizew=165)
(1)证明:
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829f9180ddd9aa1a0ee0dc520f4e0b5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/3/97e305e8-d789-4b54-a36b-cb69e8b2f3c5.png?resizew=165)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b28b5b7b3ce8cfd88c3428883bd0852e.png)
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名校
【推荐3】如图所示,平面
平面
,且四边形
是矩形,在四边形
中,
,
,
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/9/550acaa8-42bf-4207-9cb2-3d5f442e58d7.png?resizew=166)
(1)若
,求证:
平面
;
(2)若直线
与平面
所成角为
,求平面
与平面
所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c0db1f4f666a9be9ede868065a50997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbc56d42b003cbcb1fbe5c50e55b26b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7dbf31dfd36aa456a63bafea8bc1985.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a17625a53ddd11b62e9439675d391f15.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/9/550acaa8-42bf-4207-9cb2-3d5f442e58d7.png?resizew=166)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69c637be66cca06c78fa68885a7a0256.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ac480d8d9d7821b62a603cf5cfda236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ae8768996ca9a0f2c5d9a19abbd54df.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/037fb348109dc2063a268b10eb925a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/926584088b939200d88e64318f2d4e6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a09d9d486b7f91ba933210dd013a7f2c.png)
您最近一年使用:0次
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【推荐1】如图,四边形
和
都是正方形,且平面
平面
,
、
分别是
、
的中点,点
在线段
上.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/2c2aad04-f76b-4ada-a208-3f9d0c5aa16a.png?resizew=164)
(1)求证:
;
(2)若二面角
的大小为45°,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf9a6db3571fa57bfa2d5e4d44c51b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/2c2aad04-f76b-4ada-a208-3f9d0c5aa16a.png?resizew=164)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da78c917ab3631b4a5ba70ef76eb4219.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e62555c64bf39344c114f8e08bca6ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22ce50ba5e349425274f05d46d120a74.png)
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名校
【推荐2】如图.在平行四边形
中,
,
,把
沿对角线
折起,使得平面
平面
后.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/24/8a848dca-0596-4731-9b4f-d84e24818299.png?resizew=281)
(1)求
的长;
(2)求异面直线
与
所成的角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37a5c50902bea0e8e563fe156fb33d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5a588bbcb6434e8e1c703219751a401.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6f2386a332d8fbacc59cb577c14237a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/069fb06e0428a1cb2b4ce4c17eeab7fc.png)
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(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
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