名校
1 . 已知三棱柱
中,
,
,
平面
,
,
为
的中点,
为
上一点.请用空间向量知识解答下列问题:
(1)求证:
平面
;
(2)当
为
的中点时,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26cb239a35eb1f0563b5863d986859bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b10134e7a46e6f6f7cb9d5e2371727d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/25/427635e6-17c0-420a-ac8a-8d864acf7e67.png?resizew=160)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44b190c8d3d7d7d0e6e959e8a52eae90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92e31d02b38f82bfa005385f1e17d364.png)
您最近一年使用:0次
名校
2 . 已知在多面体
中,
,
,
,
,
且平面
平面
.
(1)设点F为线段BC的中点,试证明
平面
;
(2)若直线BE与平面ABC所成的角为
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/066cd386723885c535ea720f5817847a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0028211551dd418eaaf51dde450f8b73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5545dc3211671941048034af38092fa6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/236c134aad7d9a21c49c07e924b9a531.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de8ff58f671a287701011a1b31e67e28.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/21/eee2123a-b085-465b-a604-374e6bef3b4f.png?resizew=168)
(1)设点F为线段BC的中点,试证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a5f445af1ae136773cb338920552ff2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)若直线BE与平面ABC所成的角为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d5bca00fa20e6e80480b9d06d2e52ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd29cc627d76412c236aac6b29fa0fdf.png)
您最近一年使用:0次
2023-09-19更新
|
2020次组卷
|
21卷引用:陕西省宝鸡市虢镇中学2022-2023学年高三上学期第五次模考理科数学试题
陕西省宝鸡市虢镇中学2022-2023学年高三上学期第五次模考理科数学试题湖北省“荆、荆、襄、宜四地七校考试联盟2019-2020学年高三上学期10月联考数学(理)试题福建省厦门外国语学校2019-2020学年高三上学期12月月考数学(理)试题江西省新余市2019-2020学年高三上学期第四次段考数学(理)试卷内蒙古霍林郭勒市第一中学2021-2022学年高二下学期期中考试数学试题(已下线)高二上学期期中【常考60题考点专练】(选修一全部内容)-2022-2023学年高二数学考试满分全攻略(人教A版2019选修第一册)重庆市涪陵区部分学校2023-2024学年高二上学期第一次月考数学试题广东省广州市第八十九中学2023-2024学年高二上学期10月月考数学试题重庆市广益中学校2023-2024学年高二上学期10月月考数学试题四川省成都市实验外国语学校2023-2024学年高二上学期第一阶段考试数学试题辽宁省沈阳市第十五中学2023-2024学年高二上学期12月月考数学试题四川省遂宁市蓬溪中学校2023-2024学年高二上学期12月月考数学试题福建师范大学第二附属中学2020届高三上学期期中考试数学(理)试题河北省唐县第一中学2021-2022学年高二下学期期中数学试题浙江省杭州市、宁波市部分学校2022-2023学年高三下学期4月联考数学试题河南省开封市五县2023-2024学年高二上学期期中联考数学试题(已下线)第一次月考检测模拟试卷(原卷版)云南省大理州民族中学、怒江州民族中学2024届高三上学期第一次联合考试数学试题四川省宜宾市第四中学校2023-2024学年高二上学期期末数学试题四川省凉山州宁南中学2023-2024学年高二上学期期末模拟数学试题(三)北京市海淀区首都师范大学附属中学2023-2024学年高二上学期期中考试数学试题
名校
3 . 如图,在三棱柱
中,
底面
,
,
,
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/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14d355b4c58b4e883b9e65cc6da8622e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470c4e195cf7a07b7a331ce4b436e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/24/35aee009-af3f-42b8-9fd6-29aa776f52d1.png?resizew=161)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1885efcff0b903e314057dd153578600.png)
您最近一年使用:0次
2023-08-23更新
|
743次组卷
|
2卷引用:陕西省渭南市富平县2023届高三上学期摸底理科数学试题
解题方法
4 . 如图,正三棱柱的所有棱长都为
,
为
中点.用空间向量进行以下证明和计算:
(1)求证:
平面
;
(2)求二面角
的正弦值;
(3)求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/15/f870e198-8909-4c0c-8801-254d09411b09.png?resizew=180)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4560fa4ad459b58b723c74bd24e51ebf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f97babc2abb18c1540d3a5504f7cf3fe.png)
(3)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
您最近一年使用:0次
解题方法
5 . 如图,在四棱锥
中,底面
是边长为
的正方形,
底面
,
,
为
的中点,
为
的中点,建立适当的空间坐标系,利用空间向量解答以下问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/15/e9237b4d-4815-4098-9252-0bf40e60a704.png?resizew=149)
(1)证明:直线
平面
;
(2)求异面直线
与
所成角的大小;
(3)求直线
与平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06a5faf3cbb633fc4294c8ce703c64c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4317430d5a2b61d9a2a88b73e7d7ad39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9774f83067ed956a551bc41adcce0469.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/15/e9237b4d-4815-4098-9252-0bf40e60a704.png?resizew=149)
(1)证明:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f367fb956c36978b6d783e2254c2d4b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3201d3796ed9a29338aac25245a7c8e2.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be2e2c0d4ac2bd79f6cea7a9b1a50662.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3201d3796ed9a29338aac25245a7c8e2.png)
您最近一年使用:0次
11-12高二下·福建泉州·期末
名校
解题方法
6 . 如图,直三棱柱
中,
分别是
的中点,
,则
与
所成角的余弦值为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a30de2a3fd4dc9ce28ff730edf9bfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4fb1884afa6b9d2625b489d6a0b4667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebb0bc9dca69c84a5ebc6c335b02c6af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/1/02710065-7faa-4913-8031-7c7a192c2530.png?resizew=152)
您最近一年使用:0次
2023-02-24更新
|
1038次组卷
|
15卷引用:陕西省咸阳市礼泉县第二中学2022-2023学年高二上学期第二次月考理科数学试题
陕西省咸阳市礼泉县第二中学2022-2023学年高二上学期第二次月考理科数学试题天津市蓟州区2022-2023学年高二上学期期中数学试题广东省陆丰市龙山中学2022-2023学年高二下学期3月月考数学试题天津市部分区2022-2023学年高二上学期期中数学试题(已下线)2011-2012学年福建安溪梧桐中学、俊民中学高二下期末理科数学试卷天津市西青区2022-2023学年高二上学期期末数学试题广东华南师大附中中学2022-2023学年高二上学期期末数学试题山东省临沂市莒南第一中学2022-2023学年高二上学期期末数学试题广东省华南师范大学附属中学2022-2023学年高二上学期期末考试数学试题(已下线)拓展二:异面直线所成角,直线与平面所成角,二面角问题(精讲)-【精讲精练】2022-2023学年高一数学下学期同步精讲精练(人教A版2019必修第二册)(已下线)专题训练:线线角、线面角、面面角求解(已下线)13.2.2 空间两条直线的位置关系-2022-2023学年高一数学《考点·题型·技巧》精讲与精练高分突破系列(苏教版2019必修第二册)(已下线)第一章 空间向量与立体几何单元测试(巅峰版)-【冲刺满分】2023-2024学年高二数学重难点突破+分层训练同步精讲练(人教A版2019选择性必修第一册)贵州省遵义市仁怀市仁怀六中2023-2024学年高二上学期期中数学试题四川省成都市第七中学2023-2024学年高二上学期期末复习数学试题(一)
名校
7 . 如图,已知圆锥
,AB是底面圆О的直径,且长为4,C是圆O上异于A,B的一点,
.设二面角
与二面角
的大小分别为
与
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/1/c98fcac6-5de2-4237-83ea-e8653b1e73e1.png?resizew=201)
(1)求
的值;
(2)若
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/967f74b8993c61634ceed95edca05ffd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf29d07c3751c41ab3503065a5a5052e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b796bbaeb8450404c2d146283562006e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/1/c98fcac6-5de2-4237-83ea-e8653b1e73e1.png?resizew=201)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5458c30dbb22889ed27b78ae92f89e78.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf76792693c3d26302f7631276f14398.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a438393ddfc7da1804baf4932442bb35.png)
您最近一年使用:0次
2023-02-24更新
|
1843次组卷
|
9卷引用:陕西省汉中市某校2022-2023学年高三上学期第三次质量检测理科数学试题
陕西省汉中市某校2022-2023学年高三上学期第三次质量检测理科数学试题江苏省新高考基地学校2021届高三下学期4月第二次大联考数学试题江苏省连云港市灌南高级中学2023届高三下学期3月解题能力竞赛数学试题(已下线)2021年秋季高三数学开学摸底考试卷03(江苏专用)山东省日照市2023届高三一模考试数学试题河南省安阳一中、鹤壁高中、新乡一中2023届高三下学期联考理科数学试题(已下线)山东省日照市2023届高三一模考试数学试题变式题17-22重庆市七校2023届高三三诊数学试题湖南省衡阳市第八中学2023届高三高考适应性考试数学试题
名校
解题方法
8 . 如图,在四棱锥
中,底面
为矩形,
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/17/5f0d7f00-d30a-4173-a266-90dac832ac88.png?resizew=140)
(1)证明:平面
平面
;
(2)若
为
中点,求二面角
的平面角的余弦值.
![](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/6666079cf2c78be72f3f5e5f46e1031c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/17/5f0d7f00-d30a-4173-a266-90dac832ac88.png?resizew=140)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf9a6db3571fa57bfa2d5e4d44c51b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a4d781525777c7b5284dffc70b2a28a.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1a86cd1f401153b192de90246f4da53.png)
您最近一年使用:0次
2023-02-14更新
|
146次组卷
|
4卷引用:陕西省榆林市府谷中学2022-2023学年高二上学期第二次月考理科数学试题
陕西省榆林市府谷中学2022-2023学年高二上学期第二次月考理科数学试题内蒙古乌兰浩特市第四中学2022-2023学年高二下学期第一次月考数学(理)试题青海省西宁市大通回族土族自治县2022-2023学年高二上学期期末考试数学(理)试题(已下线)陕西省西安市铁一中学2023-2024学年高三上学期第二次月考理科数学试题变式题19-22
名校
9 . 如图,已知三棱柱
中,
,
,
,设
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/26/c3220273-f722-43df-81c8-ce1441647f01.png?resizew=177)
(1)若
为
的中点,求证:
;
(2)求异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90e17995e2f71e297d94ae51c7e5b1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdafc56f500b3e3772f544c8c5fb7ac2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f3adc4ed291596abf3bb93ae7a075d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cc03a3ba496faee748a8d63e5d4fa92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8780f5b68f8907a57c1c2f96233a78c5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/26/c3220273-f722-43df-81c8-ce1441647f01.png?resizew=177)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db88f93f858cca1c17d5cb3d67e22684.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
您最近一年使用:0次
2023-02-14更新
|
467次组卷
|
3卷引用:陕西省榆林市府谷中学2022-2023学年高二上学期第二次月考理科数学试题
名校
10 . 如图,直三棱柱
中,
,
,
分别是棱
,
,
的中点,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/18/c5b40ebf-d768-49e6-b3ab-4bdbc876dfa6.png?resizew=157)
(1)求证:
平面
;
(2)求平面
与平面
所成二面角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6795cae2df43a722e1355e9562d93c09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca036d049f5205cf04cb1b9c5cd03f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d927585a17c2e98ef7d5a9589a26ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/18/c5b40ebf-d768-49e6-b3ab-4bdbc876dfa6.png?resizew=157)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0f856654f9deb4c1a04e920983278c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0278f9809e118b80c9946d9b9ae40c83.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c286ed092f6e89b838c35d33adc1bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0278f9809e118b80c9946d9b9ae40c83.png)
您最近一年使用:0次