如图,在四棱锥
中,
平面
,
,底面ABCD是边长为4的菱形,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eee296a7d9fba487f1485c61580196f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/29/795f868f-ed75-4857-8a92-b366d4066bc5.png?resizew=143)
(1)求证:
;
(2)求平面PAC与平面PCD夹角的余弦值.
![](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/c19f0fcacac715a1200770516d1e4a67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eee296a7d9fba487f1485c61580196f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/29/795f868f-ed75-4857-8a92-b366d4066bc5.png?resizew=143)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb5d56d8170b764b80a672cd6c861921.png)
(2)求平面PAC与平面PCD夹角的余弦值.
更新时间:2023-01-13 00:09:49
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】三棱柱
中,平面
平面
,
,
,
,点F为棱
的中点,点E为线段
上的动点.
![](https://img.xkw.com/dksih/QBM/2020/7/9/2502366351589376/2503486277246976/STEM/c0d3db1e-7f76-4841-aec7-6ce1ffc600da.png)
(1)求证:
;
(2)若点E为线段
的中点,求点C到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac4fb99967c46a3855bcf2885b448c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08c0e1740972a1ca726eb21e32637327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1418a51d0d8bb2017ba82aa415c9f5d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b83a71cff8e2ed9c2c93ed91a5d48671.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7410727e22a3287d19ca5df0666fcd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b10b969819d397711310c8dbb399ebc.png)
![](https://img.xkw.com/dksih/QBM/2020/7/9/2502366351589376/2503486277246976/STEM/c0d3db1e-7f76-4841-aec7-6ce1ffc600da.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc90fee532e50d319081d571410421.png)
(2)若点E为线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b10b969819d397711310c8dbb399ebc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
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解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】在长方体
中,
,
,
是棱
上的点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/0081dde3-1880-4a9b-ab37-b0a264264dfc.png?resizew=140)
(1)求三棱锥
的体积;
(2)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829018a6ca0aff95d89e3f7cd943274e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41fd676c41d2d644928f014b0fea4689.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f92d8e0c3c68eecfdfad9fa8381adc4e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/0081dde3-1880-4a9b-ab37-b0a264264dfc.png?resizew=140)
(1)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b9fac14c8330781420fa076b2e04e77.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d26d8a9d64ad3c8cba28840b41ed7837.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
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解答题-问答题
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适中
(0.65)
【推荐1】如图,四面体
中,平面
平面
,
,
,
,
(1)若
,证明:
平面
;
(2)设过直线
且与直线BC平行的平面为
,当
与平面
所成的角最大时,求平面
与平面
的夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3d7090639341730951c1bc3c9b6164e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98e486a1aad96167ff62f6fb5136e0bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/037b342a682cbd4241855a243da3c016.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/24/82865398-fb61-4b93-8e67-7646787d4812.png?resizew=145)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9060f03b9ee41d70d135b1e1a8902ce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f30533da2e1d2a958dc906c37eba9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)设过直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
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适中
(0.65)
名校
【推荐2】如图,多面体
中,
,
,
为
的中点,四边形
为矩形.
![](https://img.xkw.com/dksih/QBM/2022/3/2/2927732822646784/2932379585740800/STEM/61e6eccc-b434-43ca-a6a1-e049566d44c7.png?resizew=176)
(1)证明:
;
(2)若
,
,当三棱锥
的体积最大时,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dff800bc740bbdf43a8893586c601c01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cbfc35fc915ac7d4dc017e60ccdecbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
![](https://img.xkw.com/dksih/QBM/2022/3/2/2927732822646784/2932379585740800/STEM/61e6eccc-b434-43ca-a6a1-e049566d44c7.png?resizew=176)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31b2cc1d0bfd22c88286880b9da1f6f4.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f86c589939053ce21ce0a67cf40054a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/199098479c92e87304b91871172d46e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f8c7b6766f0581fcd1ecd332afcfae.png)
您最近一年使用:0次
解答题-证明题
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适中
(0.65)
名校
【推荐1】如图,在四棱锥
中,底面
为长方形,
底面
,
,
,
为
的中点,
为线段
上靠近
点的三等分点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/bbdd65f8-99de-4904-9b0e-0e22554a5981.png?resizew=149)
(1)求证:
平面
;
(2)求平面
与平面
所成二面角的正弦值.
![](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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9a4950a6e4202efd609507964af238b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f8eeeea1c9652cacce976f8129cf520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/bbdd65f8-99de-4904-9b0e-0e22554a5981.png?resizew=149)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
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解答题-证明题
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适中
(0.65)
【推荐2】如图4,四边形
为正方形,
平面
,
,
于点
,
,交
于点
.
平面
;
(2)求二面角
的余弦值.
![](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/728dd7fac41e469ff3e1a1dbe59fb50c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f392902d611863c6908a48e696e7bd8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdd3699fbb7a8ba3f792cceb24719f71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac0b72906641ed13716cfbce50923282.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fa3254460ecbacecb3e57c5dce227f4.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9726261c25e7086835912c0d4815d270.png)
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