如图,在三棱锥
中,底面
是等边三角形,
为
边的中点,
平面
,点
在线段
上.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/c94abc1d-3de1-4ba4-b115-49a89462bf13.png?resizew=152)
(1)证明:
;
(2)若
,直线
和平面
所成的角的正弦值为
,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.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/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e126c16032892966489053f44b9048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/c94abc1d-3de1-4ba4-b115-49a89462bf13.png?resizew=152)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90dbe55407b556be48d67cde5c5dc94f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7809a0611650cea73b90fc526018935.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2a698891d42c70b597f0da4f215f09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
更新时间:2019-04-24 20:24:13
|
相似题推荐
【推荐1】如图,在直三棱柱
中,
是正三角形,
是棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/14/f746cda1-6635-43d4-993b-ffd5802bd0e9.png?resizew=204)
(1)求证平面
平面
;
(2)若
,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
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(1)求证平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3837007567ab66f5cbe93ea39d6b259.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0af405392c66b86550a58f1cb9868717.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea848cd2aa3a464618020475097949fc.png)
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解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,在四棱锥
中,底面
是菱形,
,
,
,
底面
,
,点
在棱
上,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/5f861a4f-d7cb-4a21-8a71-6b1bc5b4be21.png?resizew=216)
(1)证明:平面
平面
;
(2)求二面角
的余弦值.
(3)求四面体
的体积.
![](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/05740f0c6071846227dc0ec177ad15e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a23f01af749100e1888bba06268843db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e126c16032892966489053f44b9048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae890f9e8b32aa53a54158f24f4a87bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cc72a44dad13532cb9ddcc64bd78105.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/5f861a4f-d7cb-4a21-8a71-6b1bc5b4be21.png?resizew=216)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f04c222223dae9ef27d4c132534d9848.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c66d99a6a8415ddad22bbed33b64cfb.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5102c216393e133fa25dba98cd78535.png)
(3)求四面体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f178906e90bafd73e0ef9f89814855d5.png)
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解答题-问答题
|
适中
(0.65)
【推荐1】如图所示,已知线段AB在平面α内,线段AC⊥α,线段BD⊥AB,且AB=7,AC=BD=24,线段BD与α所成的角为30°,求CD的长.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/1b3a1c0e-a4ce-4317-9386-f18724fcf642.png?resizew=162)
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解答题-证明题
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解题方法
【推荐2】如图,
与平面
斜交,点
为斜足,
为
在
内的射影,
为平面
内过点
的任一条直线.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48fce10478485ef01d2318fc3465bb4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09b83e3cde63d2246491ee82c2aff244.png)
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您最近一年使用:0次