如图,在三棱锥
中,
是等边三角形,
,点
是
的中点,连接
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/5d30685d-39d4-43d7-841d-f1cb6b99db3e.png?resizew=190)
(1)证明:平面
平面
;
(2)若
,且二面角
为
,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23b6e08fde74010412a6f14ad4dfbcc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/553ec13b2451a004fa4417425e59588a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/5d30685d-39d4-43d7-841d-f1cb6b99db3e.png?resizew=190)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17580410bf63dba4fe164265afaac4cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c54d01623f09f23103f03ba1135fc6a.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29470a095de205acb450d5a48b38be1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f1854ba6cc92481d7a616bd2788a47e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c0927afc571a7c966c98192040979e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
2020·河南·模拟预测 查看更多[7]
2020届河南省高三普通高等学校招生模拟考试理科数学试题四川省成都市石室中学2021-2022学年高三上学期专家联测卷(二)数学(理)试题(已下线)专题24 立体几何解答题最全归纳总结-2第三章 空间向量与立体几何单元检测A卷 (基础篇)湖北省咸宁鲁迅学校2023届高三下学期5月月考数学试题(已下线)重难点突破06 立体几何解答题最全归纳总结(九大题型)-2(已下线)专题15 立体几何解答题全归类(练习)
更新时间:2020-03-15 23:06:23
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解答题-问答题
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(0.94)
名校
【推荐1】如图,AB是圆O的直径,点C是圆O上的动点,过动点C的直线SC垂直于圆O所在的平面,D,E分别是SA,SC的中点.
证明:
平面ABC
平面
平面SBC
证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1fc20fb331b3caeea769b366ee3d7cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65863c1abad833b79c303bfca24f535c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d817db39541bf3eecc5bdfd3b04991c4.png)
![](https://img.xkw.com/dksih/QBM/2018/12/7/2091540642529280/2092631607427072/STEM/3456c9abfeb8487684c5a731b771906a.png?resizew=163)
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解答题-证明题
|
容易
(0.94)
解题方法
【推荐2】如图,四棱锥P-ABCD的底面是菱形,且PA
面ABCD,E,F分别是棱PB,PC的中点.
![](https://img.xkw.com/dksih/QBM/2021/10/26/2837829092679680/2839312348872704/STEM/0343d2435839487d877a646bffea60bc.png?resizew=187)
求证:(1)EF
平面PAD;
(2)面PBD
面PAC.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://img.xkw.com/dksih/QBM/2021/10/26/2837829092679680/2839312348872704/STEM/0343d2435839487d877a646bffea60bc.png?resizew=187)
求证:(1)EF
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
(2)面PBD
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
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解答题-问答题
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解题方法
【推荐1】在直三棱柱ABC﹣A1B1C1中,AB⊥AC,AB=AC=2,A1A=4,点D是BC的中点;
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/2/ca0fd250-5508-4110-b1f5-65666baba906.png?resizew=136)
(I)求异面直线A1B,AC1所成角的余弦值;
(II)求直线AB1与平面C1AD所成角的正弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/2/ca0fd250-5508-4110-b1f5-65666baba906.png?resizew=136)
(I)求异面直线A1B,AC1所成角的余弦值;
(II)求直线AB1与平面C1AD所成角的正弦值.
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解答题-证明题
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容易
(0.94)
名校
【推荐2】如图1,在平面四边形
中,已知
,
,
,
,
,
于点
.将
沿
折起使得
平面
,如图2,设
(
).
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/8df9f93a-285a-44d5-81bf-e1c7e9596a20.png?resizew=289)
(1)若
,求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
平面
;
(2)若直线
与平面
所成角的正弦值为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4864c21e9664fa9111ede6425b09563a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da48240e7fc3248f773ac1500c15ec14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37002ada5d194d4d062fa3285d7d9824.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f71f070c1aa967a945113735322fae18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9295bfd1b7085a86d874617d5f87f099.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6be8ab51eec310bfd7d6c01cc311c53.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.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/94bd29473c0065517b9427d0147d1c49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd3ede869e508a8c8bda34a16782f863.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/8df9f93a-285a-44d5-81bf-e1c7e9596a20.png?resizew=289)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/441809d6ce2df21a85b390cdce9b1112.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb304d905125170bebfada27e7ed8960.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1174142f3bba761585b6bc2653009b36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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