如图,在三棱柱
中,
,
,D,E分别是CB,CA的中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/19/b13d9e2d-c34b-4c78-83db-681c10945d10.jpg?resizew=164)
(1)若平面
平面
,求点
到平面ABC的距离;
(2)若
,求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9332278351ab92e03e984e9279dd06a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45224f7eac9d0cef64bf28d93e7721a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fec64454070a31334375468ad17d2eb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/19/b13d9e2d-c34b-4c78-83db-681c10945d10.jpg?resizew=164)
(1)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61cdaadeae37736a1e6dd93fa1fe712f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1225db7039505351a11f64841ec0af2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
更新时间:2023-12-20 21:25:35
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】1.如图所示,已知平行四边形
中,
,
,
,
,垂足为
,沿直线
将
翻折成
,使得平面
平面
;连接
,
是
上的点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/19/b5491256-fa9a-451f-a754-8776122f48be.png?resizew=494)
(1)当
时,求证:
平面
;
(2)当
时,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d79e7020414add95907e061df505ef0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6da5fbf1298eca6853f9febfd4a07440.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e3f5dc11efe60b4fd9a13b1d6b83842.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad09a769a75b107390b9eeccc929f761.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cb0a272d6917c569c36b60dd9ec8094.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73612d2cce34e663255c76ccab2d892a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6bfad3f7e65188bcf7f62ea5acdbf4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab41cce6eb2d3058a644314865d16548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab41cce6eb2d3058a644314865d16548.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/19/b5491256-fa9a-451f-a754-8776122f48be.png?resizew=494)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07d047a406fbf8cd353a5aed9bf0c85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e245440d3761fb4217eaa8dc303fa288.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47ce36044e81456a40b5f63749c814e5.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52ddbc03b14bc6a863989f2ab6048e3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/471c511dc9f95ac5eb4784a105aee9e0.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图,在四棱锥
中,
底面
,底面
是直角梯形,
,
点在
上,且
,点
在
上,且
.
![](https://img.xkw.com/dksih/QBM/2022/1/19/2897681419952128/2899965933977600/STEM/15018044-7c17-47bb-a541-4eefecc55e1e.png?resizew=166)
(1)求证:平面
平面
;
(2)若直线
与平面
所成的角为
,求二面角
的余弦值;
(3)在第(2)问条件下,线段
上是否存在点
,使得
平面
,若存在,求出
的值,若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.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/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90ff6d7dd48b57f03d82d2c522ee9b94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57af6716734f5c1b63a9376712fcfbc7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45ab1959f7fa560977ffb9fb0e11bb2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f0ce7aaca2b6725dac7ed5d2a437aa1.png)
![](https://img.xkw.com/dksih/QBM/2022/1/19/2897681419952128/2899965933977600/STEM/15018044-7c17-47bb-a541-4eefecc55e1e.png?resizew=166)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f020ca4ad44801691235958e253907d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1e5fa72f2878b476bc57f0df12d6555.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce81faef7c631553e02d7468973a74cd.png)
(3)在第(2)问条件下,线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3843a9266bd178e87ff5e87e7f02c734.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64eb31601464364be2baf4aa87404bcd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2a4eae6cd9bd7c514e6298ddcf81001.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】四棱锥
中,
平面
,
(
),
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/ba85f28a-376b-4272-b365-88c40789310e.png?resizew=319)
(1)若
,
,
为
的中点,求证:
;
(2)若
,
,求平面
与平面
所成角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b58cae7d496a4b13f27d261d5baf48dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc166a92e4f83599269694dfe39af700.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a2efb46714efa6a13a121e2a7f89412.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/ba85f28a-376b-4272-b365-88c40789310e.png?resizew=319)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aed49ecc2b80bfb03b872742eacfccf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4217f4375caaeef4d4221143d5f6bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b190d05ba62b355d54012483a05077.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c5247cb4bcf395152043841f784722a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d42e97eee705d164e6ac6de9ecd6d1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,四棱锥
的底面
为梯形,
,
,
底面
,且
,
.
![](https://img.xkw.com/dksih/QBM/2021/1/5/2629415692427264/2632467863699456/STEM/5e7c20fc-1d4d-4fac-bdbe-db85ee42d04b.png?resizew=251)
(1)若
为
的中点,证明
平面
;
(2)点
在
上,且
,求二面角
的正弦值.
![](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/ce4ab7e657f01bdfa235f8c4d6681d13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5acb763021bf166ca719d07223591d9.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/52a923784f083b7f4777891afe06b44e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f8eeeea1c9652cacce976f8129cf520.png)
![](https://img.xkw.com/dksih/QBM/2021/1/5/2629415692427264/2632467863699456/STEM/5e7c20fc-1d4d-4fac-bdbe-db85ee42d04b.png?resizew=251)
(1)若
![](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/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f88454ace46996b99361d18e76189cdc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74011b64ff147ac2f10c36a11ac1b34d.png)
您最近一年使用:0次