1 . 如图,在几何体
中,平面
平面
,四边形
为正方形,四边形
为平行四边形,四边形
为菱形,
为棱
的中点,点
在棱
上,
平面
.
(1)证明
平面
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fee4915234cd5311d3b5e384b82caa11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e50d31a3f637f9632a947f0866eede1.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/8b4cd2b33bd983a9ed6575b9de04a46a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b808a8facf9af30cd8a083010a7b850d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d49a261ac5fac66509272f669f5728f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31c34b18525831f3eda7bb90be0199b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ae8768996ca9a0f2c5d9a19abbd54df.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/14/bddb6519-9ff9-457f-ba88-e6131b9a975e.png?resizew=161)
(1)证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8d2d217e9bcd059908f117dfc4d4259.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5888bec948373f3854258ad80171073d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ae8768996ca9a0f2c5d9a19abbd54df.png)
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2024-04-07更新
|
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2卷引用:湘豫名校联考2024年2月高三第一次模拟考试数学试题
名校
2 . 如图,在四面体
中,
,
,
、
分别是
、
的中点.若用一个与直线
垂直,且与四面体的每个面都相交的平面
去截该四面体,由此得到一个多边形截面,则下面的说法中正确的有___________ .
![](https://img.xkw.com/dksih/QBM/2022/5/3/2971674429718528/2973409103798272/STEM/dbaace67-7c33-4e3e-b46d-159b82c66b04.png?resizew=205)
①
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc90fee532e50d319081d571410421.png)
②四面体外接球的表面积为
.
③异面直线
与
所成角的正弦值为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d63d1200ef5de2c40f2022af10a87b74.png)
④多边形截面面积的最大值为
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a59ebce0d93e5617f848fe79fecb215.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f32924638bc9a40e16bdb24540e8c5ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://img.xkw.com/dksih/QBM/2022/5/3/2971674429718528/2973409103798272/STEM/dbaace67-7c33-4e3e-b46d-159b82c66b04.png?resizew=205)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab1a1fd2fc33e89f357cef772ff6cd0e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc90fee532e50d319081d571410421.png)
②四面体外接球的表面积为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b18b085fd6dbc65b54eeb98fb65393c.png)
③异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d63d1200ef5de2c40f2022af10a87b74.png)
④多边形截面面积的最大值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c0874f019492261eb175bdcc08c189d.png)
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2022-05-06更新
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7卷引用:河南省南阳市第一中学校2021-2022学年高三下学期第五次月考理科数学试题
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