1 . 如图,在四棱锥
中,底面
是矩形,
是
的中点,
与
交于点
,
平面
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/4b0ef387-0ca9-40b8-a3e3-93b07a9f4da2.png?resizew=190)
(1)求证;平面
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4049cbab185d39f80f4fe731c65def78.png)
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15a424b50eaeafa6f302ffd95476cb86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d30637da200a07672ae231b4c5c09cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04be58ea6ca37a850422631eb3e994d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d4746df85049d1651d3f6c30212a7a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a727432fbf5b502786cdb18b84b8920.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/4b0ef387-0ca9-40b8-a3e3-93b07a9f4da2.png?resizew=190)
(1)求证;平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78307cd417504554a4e2276fe24d1162.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4049cbab185d39f80f4fe731c65def78.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d4db9b82b67efe45a02fca32bfcf5dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d923a338dd2d2e29336b42574d38448.png)
您最近一年使用:0次
2019-06-21更新
|
595次组卷
|
2卷引用:2019年重庆市高考数学模拟试卷(理科)(5月份)
2 . 如图,四棱锥
中,底面
是边长为2的正方形,侧面
底面
,
为
上的点,且
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf4c26f3f4d96117f087400a0f32ece8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/914d2774-52dc-4be8-9a2e-42499e4542d8.png?resizew=139)
(1)求证:平面
平面
;
(2)当三棱锥
体积最大时,求二面角
的余弦值.
![](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/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/662698361c6b3ddaf0c28a3c87be53e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf4c26f3f4d96117f087400a0f32ece8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/914d2774-52dc-4be8-9a2e-42499e4542d8.png?resizew=139)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)当三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e67a35615a7a9b3aeb0212a62cef30.png)
您最近一年使用:0次
2019-05-22更新
|
1669次组卷
|
4卷引用:2019届重庆市南开中学高考模拟(7)理科数学试题
真题
3 . 如图,四棱锥
中,底面是以
为中心的菱形,
底面
,
,
为
上一点,且
.
(1)求
的长;
(2)求二面角
的正弦值.
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/c2f70fe100034862ad6a8d5165d3db75.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/9874f5fd78824379bc461e831765222c.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/666341487fc24fe894dd5693b5423d70.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/c285cf021e4146ea9257c0acf215d626.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/5e24b055d96e44bfb1379179ae66437d.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/e8e14784d9d94c5298c601d73e447b85.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/a83d9b34c6924cca9a9813d7d0411cf1.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/0b2dbced52bc4937b20069a722f436af.png)
(1)求
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/542f6e6aab214cde92cb47df27649862.png)
(2)求二面角
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571784957353984/1571784963276800/STEM/e480f142b1dd41fd9ababe1b594f8627.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/10/c5a93352-2096-4256-abb2-0c6023565c6a.png?resizew=218)
您最近一年使用:0次