名校
解题方法
1 . 如图,在平行六面体
中,底面
是矩形,
,
.
(1)求证:
平面
;
(2)从下面三个条件中选出两个条件,使得
平面
,
(ⅰ)并求平面
与平面
夹角的余弦值;
(ⅱ)求点B到平面
的距离.
条件①平面
平面
;②平面
平面
;③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebe236a434aa88e5633ea61574d1bed8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/10/e6a8f9a3-0f89-492f-be16-a12a902b1ef0.png?resizew=160)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb689000fa7a3b425be3196d8b0f32af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fae7f4612c548b1f72a964ddb291cd2e.png)
(2)从下面三个条件中选出两个条件,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a8bfe2553e852df73185d017c0a62fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(ⅰ)并求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fae7f4612c548b1f72a964ddb291cd2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(ⅱ)求点B到平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fae7f4612c548b1f72a964ddb291cd2e.png)
条件①平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfc2810e0d0be3d1f09c79d7a1832d38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/433b5f967c7a8bfdb1dc8c6addcced5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6c3552c858a6f061cd926738d646a3e.png)
您最近一年使用:0次
2024-01-15更新
|
388次组卷
|
2卷引用:北京市东城区广渠门中学2024届高三上学期12月月考数学试题
名校
2 . 在正四棱柱
中,
,
是棱
上的中点.
(1)求证:
;
(2)异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56b66218bbfb24acee762d795831e42c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/28/56f1fa7d-2b62-4c27-ab33-8062918930d5.png?resizew=130)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52ab924e3692515bd8be4c36472a959a.png)
(2)异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
您最近一年使用:0次
2023-10-20更新
|
2769次组卷
|
16卷引用:北京市丰台区2022-2023学年高二上学期数学期末练习数学试题
北京市丰台区2022-2023学年高二上学期数学期末练习数学试题北京市朝阳区东北师范大学附属中学朝阳学校2023-2024学年高二上学期第一次学习质量监测与反馈数学试题四川省雅安市雅安中学2022-2023学年高二下学期期中数学(理)试题第一章 空间向量与立体几何 (单元测)福建省仙游县枫亭中学2022-2023学年高二下学期期中考试数学试题河南省郑州市基石中学2022-2023学年高二下学期期中数学试题江苏省南通市如皋中学2024届高三创新实验班夏令营数学试题(已下线)第三章 空间向量与立体几何(基础巩固检测卷)-2023-2024学年高二数学同步精品课堂(北师大版2019选择性必修第一册)湖南省长沙市德成学校2023-2024学年高二上学期10月月考数学试题海南省川绵中学2023-2024学年高二上学期10月第一次月考数学试题山西省运城市景胜中学2023-2024学年高二上学期10月月考数学试题(A卷)广东省佛山市顺德德胜学校2023-2024学年高二上学期期中数学试题广西壮族自治区桂林市灵川县广西师大附中2023-2024学年高二上学期段考(期中)数学试题河南省三门峡市渑池县第二高级中学2023-2024学年高二上学期第二次月考(11月)数学试题湖南省张家界市民族中学2023-2024学年高二上学期第二次月考数学试题(已下线)考点12 空间角 2024届高考数学考点总动员 【讲】
名校
3 . 如图,在四棱锥
中,
,
平面
,底面
为正方形,
,
分别为
,
的中点.
(1)求证:
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1365206d14224e0b2d40a7bd8b7965ac.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/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/4/578e3534-c0e1-4c0f-8a35-d416eab64d16.png?resizew=141)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8c2b786c64e6a9ed2ec5670cde74f86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/588690c4a218025937357ffab8d63c7a.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/588690c4a218025937357ffab8d63c7a.png)
您最近一年使用:0次
2023-10-17更新
|
389次组卷
|
12卷引用:北京市朝阳区北京工业大学附属中学2023-2024学年高二上学期10月月考数学试题
北京市朝阳区北京工业大学附属中学2023-2024学年高二上学期10月月考数学试题2020届北京市高考适应性测试数学试题北京师范大学亚太实验学校2021届高三上学期期中数学试题北京市第四十三中学2021届高三1月月考数学试题西藏拉萨市2020届高三第二次模拟考试数学(理)试题(已下线)专题19 立体几何综合-2020年高考数学(理)母题题源解密(全国Ⅲ专版)(已下线)专题20 立体几何综合-2020年高考数学(理)母题题源解密(全国Ⅱ专版)黑龙江省哈尔滨市第九中学校2020-2021学年高二上学期期中考试数学(理)试题天津市河西区梧桐中学2020-2021学年高二上学期第一次学情调研数学试题福建省尤溪县第五中学2021-2022学年高二上学期第一次月考数学试题云南省砚山县第三高级中学2021-2022学年高二上学期期末考试数学试题云南省昭通市一中教研联盟2023-2024学年高二上学期期末质量检测数学试题(B卷)
名校
4 . 如图,在直角梯形
中,
,
,
.以直线
为轴,将直角梯形
旋转得到直角梯形
,且
.
平面
;
(2)在线段
上是否存在点
,使得直线
和平面
所成角的正弦值为
?若存在,求出
的值;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2b377f22aafd3742ad860f77abaacef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/555e29e445c95ddb514840f63fbb1d12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f345b28a81ff3d2c4666ee945a426fa9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40f44f2b2f82a9126223138972850aa2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1b489c25405ce48699d4f0a62820bed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24c14ff9b66f21c05e52dc3c8908c2df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc8f45af58d68d63aeebf7ea8ecfac4.png)
您最近一年使用:0次
2023-10-17更新
|
1446次组卷
|
7卷引用:北京市第五中学2024届高三上学期10月月考数学试题
5 . 如图,长方体
中,
,
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/5/b7c2b5c9-56cb-49de-a1f9-5e4e81e8a988.png?resizew=150)
(1)求证:直线
面
;
(2)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c52ba95a39d97385ac6835b25ddabe6b.png)
(3)求二面角
的余弦值;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27db558e8db4c957654c8e5cecd2d2dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55a2310cbba5e050488cd9296eb195d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/5/b7c2b5c9-56cb-49de-a1f9-5e4e81e8a988.png?resizew=150)
(1)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16f7f44fa920f5758bc72b182ac9d181.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e48e2f18c4c61dfcc908827ac3c8a204.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c52ba95a39d97385ac6835b25ddabe6b.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a175800417614231410d9c86a9c21591.png)
您最近一年使用:0次
解题方法
6 . 直三棱柱
中,点M、N分别为
、
中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/6/d54d7929-e2d3-471a-a482-d508a9e1ce6c.png?resizew=162)
(1)求证:
平面
;
(2)已知
,
,
.
(ⅰ)求直线
与平面
所成角的正弦值;
(ⅱ)求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/6/d54d7929-e2d3-471a-a482-d508a9e1ce6c.png?resizew=162)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9b7b7793d29d66dfdd89e7a6564a35c.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df209c58c4cc146ef62100e6d3b068d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
(ⅰ)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9539f8fb13345b449274b67bbda995db.png)
(ⅱ)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9539f8fb13345b449274b67bbda995db.png)
您最近一年使用:0次
名校
解题方法
7 . 如图,已知
平面
,
为矩形,
,M,N分别为线段
,
的中点.
平面
;
(2)求
与平面
所成角的正弦值.
(3)若Q是线段
的中点,求点Q到平面
的距离.
![](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/d5ef03497414d454933f76684ee16970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c5757f787d98f9a46777324b69ad672.png)
(3)若Q是线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c5757f787d98f9a46777324b69ad672.png)
您最近一年使用:0次
2024-01-05更新
|
1338次组卷
|
4卷引用:北京市丰台区怡海中学2023-2024学年高二上学期期末模拟练习数学试题(2)
北京市丰台区怡海中学2023-2024学年高二上学期期末模拟练习数学试题(2)天津市武清区杨村一中2024届高三上学期第三次质量检测数学试题(已下线)专题13 空间向量的应用10种常见考法归类(3)(已下线)信息必刷卷04(天津专用)
名校
8 . 如图,在四棱锥
中,底面
为正方形,
平面
,
,点
、
、
分别为
、
、
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/29/2757337d-ac3f-4f74-b6af-fed363b3edd9.png?resizew=162)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
平面
;
(2)求平面
与平面
所成锐二面角的余弦值;
(3)求直线
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/411b38a18046fea8e9fab1f9f9b80a5f.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/71d05cabe8b2ed458352638ef291ab45.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/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/29/2757337d-ac3f-4f74-b6af-fed363b3edd9.png?resizew=162)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffe8a84ca3a13f82aff1a022edc66065.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffe8a84ca3a13f82aff1a022edc66065.png)
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9 . 如图1所示,平面多边形
中,
,
,
,且
,现沿直线
将
折起,得到四棱锥
,如图2所示.
(1)求证:
;
(2)在图(2)中,若直线
与平面
所成角的正弦值为
,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6723f8b9d907981aa735cd96386bee36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373585f2c60ca4e176e695b360b7ba6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e7990d7f75ab69abc8a3a08365c9a72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/840d92478eeda81ed76c9c945a27a544.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a664bf10399f679b60e7e36cdf0fb08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88929f4ba0851730d5f941d426b87548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aefe4a3e7a7fa195ed6a6712447639b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d02bd5cfe804460846423e77f72db10f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/1/f46b94fe-5db2-41dc-947d-1fbf73071055.png?resizew=341)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3edc1be5141e54264eb9ade93bb8bb33.png)
(2)在图(2)中,若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3520ee9cc97a075e889e1625dba1157c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaa42621cd6793e7f3673fdb49bc3123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/840798a31aba0783f96584e0ad7c0d2e.png)
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名校
10 . 如图, 在三棱柱
中,
为等边三角形,四边形
是边长为2的正方形, D为AB中点, 且 ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50b193e9a6e49d78f89a479fd04f97a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/22/219733bf-a7ed-4c58-b52e-08bc2dd0019f.png?resizew=171)
(1)求证: CD⊥平面
;
(2)已知点 P 在线段
上,且直线AP 与平面
所成角的正弦值为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/770abdd10660689c605577f9cb6d9db1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50b193e9a6e49d78f89a479fd04f97a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/22/219733bf-a7ed-4c58-b52e-08bc2dd0019f.png?resizew=171)
(1)求证: CD⊥平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)已知点 P 在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74bca84ad86c648d3bb20c8909c8da3f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9868f77d5ab5073b6145f1c6d272122e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20ca3bdb7a6f14db41bbc013000c510a.png)
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