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解题方法
1 . 如图所示,四棱锥S-ABCD的底面是正方形,每条侧棱的长都是底面边长的
倍,P为侧棱SD上的点.
(1)求证:AC⊥SD;
(2)若SD
平面PAC,则侧棱SC上是否存在一点E,使得BE
平面PAC?若存在,求SE∶EC的值;若不存在,试说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/13/bf2e626d-6761-463f-9189-d2eb420df216.png?resizew=160)
(1)求证:AC⊥SD;
(2)若SD
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
您最近一年使用:0次
2023-06-11更新
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354次组卷
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2卷引用:安徽省黄山市屯溪第一中学2023-2024学年高二上学期10月月考数学试题
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2 . 如图,在斜三棱柱
中,点O.E分别是
、
的中点,
与
交于点F,
平![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
已知
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/17/5a3da2c0-0cd1-4a8f-b6a3-17d53c472252.png?resizew=198)
(1)求证:
平面
;
(2)求
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/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ce03b310edce42191f9fa75a1c909ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c90282d4a37c9a20620d4bbb0c263cae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a3cc9cccfb4c260dac05f4ed57e8c10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29ba708880f5eb782acbf2c961c2494c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/17/5a3da2c0-0cd1-4a8f-b6a3-17d53c472252.png?resizew=198)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc6184b191e6da43911e701121517e.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8550fbd7938e0d8639462ac52a6dad1f.png)
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