名校
1 . 如图,已知在矩形
中,
,
,点
是边
的中点,
与
相交于点
,现将
沿
折起,点
的位置记为
,此时
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/8/39a0bfcb-0355-4523-a217-5a44acf0472b.png?resizew=311)
(1)求证:
平面
;
(2)求证:
面
;
(3)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21ea52361458ce2e49ed0fe99d8e6c02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5b3bd5e6bc2a0a277d279bb01af9584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d30374a2dad85e336ceaa462be7e00e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9b123ae31090740589ba27a846620b5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/8/39a0bfcb-0355-4523-a217-5a44acf0472b.png?resizew=311)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/982d01f052709b72afeaf1015fc7acc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e536350bcd19804313eb04f43622943c.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66b1c91be4cd269b869d0fa2956b3685.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e536350bcd19804313eb04f43622943c.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d7f66b146fccec50efa1c316aa1afe0.png)
您最近一年使用:0次
2022-07-06更新
|
1128次组卷
|
6卷引用:广东省汕头市2021-2022学年高一下学期期末数学试题
广东省汕头市2021-2022学年高一下学期期末数学试题福建省福州第一中学2022-2023学年高二上学期教学质量检测(12月)数学试题 (已下线)微专题16 利用传统方法轻松搞定二面角问题(已下线)高一下学期数学期末考试高分押题密卷(五)-《考点·题型·密卷》江苏省常州市溧阳市2022-2023学年高一下学期期末数学试题江苏省常州市华罗庚中学2022-2023学年高一创新班下学期期末数学试题
解题方法
2 . 如图,四棱锥
中,
底面
.底面
为菱形,且
,
,E,M,N分别为棱
的中点.F为
上的动点,
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/67cbbc35-773c-445d-b5b8-069cfb6e2e71.png?resizew=252)
(1)求证:
平面
;
(2)若三棱锥
的体积为2,求棱
的长.
![](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/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bbaccd578a43b2397c8bdd50592fa07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19bb1063e139610045f3bca5ca0b2766.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/67cbbc35-773c-445d-b5b8-069cfb6e2e71.png?resizew=252)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)若三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40701521959f0e8f81193b9ab96e064a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
您最近一年使用:0次
2022-04-01更新
|
790次组卷
|
4卷引用:百师联盟2022届高三二轮复习联考(一)(全国卷)文科数学试题
百师联盟2022届高三二轮复习联考(一)(全国卷)文科数学试题四川省成都七中万达学校2022-2023学年高三上学期9月月考文科数学试题专题6.1 几何体的表面积与体积-2021-2022学年高一数学北师大版2019必修第二册(已下线)8.5.3 平面与平面平行 (精讲)(2)-【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)
2022高三·全国·专题练习
解题方法
3 . 如图①,在直角梯形
中,
,
,
,
为
的中点,
、
、
分别为
、
、
的中点,将
沿
折起,得到四棱锥
,如图②.求证:在四棱锥
中,
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b027ed57b9c6f24e27ec0ae282c76efa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/538de9ad824b230984e27b76417ebb45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d390782b8ea7016628ee68403dcbfbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cf60f382809c325644b9f4217de33ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.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/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/177678001b2ccde1db8f57fa5e017002.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12d8677ae5ca7acf874d93789425d172.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffe8a84ca3a13f82aff1a022edc66065.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/3ef8b4bb-1820-41c5-80c2-dd4d2f9d1cbc.png?resizew=279)
您最近一年使用:0次
2022-11-02更新
|
688次组卷
|
6卷引用:第03讲 空间直线、平面的平行 (高频考点—精讲)-2
(已下线)第03讲 空间直线、平面的平行 (高频考点—精讲)-2(已下线)8.5.3 平面与平面平行 (精讲)(2)-【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)8.5.3 平面与平面平行(精讲)-【题型分类归纳】2022-2023学年高一数学同步讲与练(人教A版2019必修第二册)(已下线)13.2.4 平面与平面的位置关系 (1)(已下线)13.2.4 平面与平面的位置关系(已下线)专题09 基本图形的平行与垂直-期中期末考点大串讲(苏教版2019必修第二册)
2022高三·全国·专题练习
解题方法
4 . 在长方体
中,
,P为
的中点.已知过点
的平面
与平面
平行,平面
与直线
分别相交于点M,N,请确定点M,N的位置;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed557e33dca77e3a0257601967aae3a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0fefcf84a963513b911531e84cb4ce3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bc9b42d16569ad69c38883534a0be16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecba79b0285803b1bc62d406d568b016.png)
![](https://img.xkw.com/dksih/QBM/2022/8/19/3047954347515904/3048534970114048/STEM/f072216f1ffc4d5abe3c4e8ad6b4cb1a.png?resizew=230)
您最近一年使用:0次
名校
解题方法
5 . 如图,在四棱锥O﹣ABCD中,OA⊥底面ABCD,且底面ABCD是边长为2的正方形,且OA=2,M,N分别为OA,BC的中点.
(1)求证:直线MN
平面OCD;
(2)求点B到平面DMN的距离.
(1)求证:直线MN
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
(2)求点B到平面DMN的距离.
![](https://img.xkw.com/dksih/QBM/2019/12/28/2372103952433152/2419518485512192/STEM/5167e8e76a084772b5eb00faef5a5804.png?resizew=180)
您最近一年使用:0次
2020-03-14更新
|
1782次组卷
|
5卷引用:专题1.4 空间向量的应用(4类必考点)
名校
解题方法
6 . 如图,已知四棱锥
中,
分别是
的中点,
底面
,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5409942c6a29b7f347e22ed656e4d1b3.png)
![](https://img.xkw.com/dksih/QBM/2021/5/11/2718965672411136/2720728923897856/STEM/e130e9f364104801bde24b28b84e692d.png?resizew=224)
(1)证明:
平面
;
(2)若
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8a3842f9e99b71d9fc4baa9c471a3da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9cd5e413cb380bfad5af472412236775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e126c16032892966489053f44b9048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5409942c6a29b7f347e22ed656e4d1b3.png)
![](https://img.xkw.com/dksih/QBM/2021/5/11/2718965672411136/2720728923897856/STEM/e130e9f364104801bde24b28b84e692d.png?resizew=224)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373f735f0f04d11f1951eaef1bb78b6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/345368a256c743818a7ca1487ae4c4f4.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae890f9e8b32aa53a54158f24f4a87bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4b5e0b8c35a7d9b3d68db8e5c89b8bd.png)
您最近一年使用:0次
2021-05-14更新
|
1207次组卷
|
6卷引用:一轮复习大题专练43—立体几何(体积2)-2022届高三数学一轮复习
名校
解题方法
7 . 如图,在四棱锥
中,平面
平面
,
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2022/4/27/2967147992440832/2974320648839168/STEM/bb190a63-d2b5-4b6b-9c77-d9bc870a2ff5.png?resizew=203)
(1)求四棱锥
的体积;
(2)在线段
上是否存在点
,使得
平面
?若存在,求
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/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68d31600cba2d5256c7e78b6122d6755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8254b52b379a420c17d38334940b073.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8e2a44d05b1d387150c4b359e021ffc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ef219a0acb1b2f8fce339ecdbeddaaf.png)
![](https://img.xkw.com/dksih/QBM/2022/4/27/2967147992440832/2974320648839168/STEM/bb190a63-d2b5-4b6b-9c77-d9bc870a2ff5.png?resizew=203)
(1)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcfacd208d769d01f1d4ef20313cd869.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29a6ce188523ed6ab24fa2bfa6e17fdb.png)
您最近一年使用:0次
2022-05-07更新
|
684次组卷
|
4卷引用:河南省豫西名校2021-2022学年高三下学期4月教学质量检测文科数学试题
河南省豫西名校2021-2022学年高三下学期4月教学质量检测文科数学试题(已下线)文科数学-2022年高考考前20天终极冲刺攻略(四) (6月1日)(已下线)第03讲 空间直线、平面的平行 (精讲)-2山东省德州市夏津育中万隆中英文高级中学2021-2022学年高一下学期第二次月考数学试题
名校
8 . 如图,在直三棱柱
中,
为
的中点.
![](https://img.xkw.com/dksih/QBM/2022/9/26/3074832366305280/3075342448058368/STEM/1b51156345f348d4901e8bdac4eafe94.png?resizew=214)
(1)记平面
与平面
时交线为
, 证明:
;
(2)求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df226b960fe63b037a0b85443fd49f98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://img.xkw.com/dksih/QBM/2022/9/26/3074832366305280/3075342448058368/STEM/1b51156345f348d4901e8bdac4eafe94.png?resizew=214)
(1)记平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af68a7bf0da4f7c6f739d2e2461ad9b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e450f5f4225c000c2e8ea1cc14c140f2.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7692c644180b475efb60304ae8f811fc.png)
您最近一年使用:0次
2022-09-27更新
|
689次组卷
|
6卷引用:考点34 二面角【理】-备战2022年高考数学典型试题解读与变式
(已下线)考点34 二面角【理】-备战2022年高考数学典型试题解读与变式江苏省扬州、盐城、南通部分学校2022届高三上学期10月第一次大联考数学试题江苏省盐城 、淮安、 宿迁 、如东等地2021-2022学年高三上学期第一次大联考数学试题福建省龙岩市第一中学2022届高三上学期第三次半月考数学试题(已下线)第53讲 章末检测八江苏省苏州市张家港高级中学2021-2022学年高三上学期期中模拟数学试题
名校
9 . 如图,在四棱锥
中,底面
为正方形,
、
、
、
分别为
、
、
、
的中点.
![](https://img.xkw.com/dksih/QBM/2022/1/5/2888023032455168/2888777436717056/STEM/4b59e41050f8425ea785f453f7596d20.png?resizew=241)
(1)证明:
平面
;
(2)若平面
平面
,
为等边三角形,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/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.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/20a541b81584a032f571159ea152c85a.png)
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![](https://img.xkw.com/dksih/QBM/2022/1/5/2888023032455168/2888777436717056/STEM/4b59e41050f8425ea785f453f7596d20.png?resizew=241)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dcafa398cc6b6079883e7ad153eb62d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6221be113e161825e54d48a2fb16d516.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/290a37874cd284fb1a8c864769ce50c9.png)
您最近一年使用:0次
2022-01-06更新
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712次组卷
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2卷引用:河北省张家口市2022届高三上学期期末数学试题
名校
解题方法
10 . 如图,在三棱柱
中,点
,
分别为
,
上的动点,若平面
平面
,请问
是否为定值.若为定值求出该值,若不是定值,说明理由.
![](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/6795cae2df43a722e1355e9562d93c09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/139b59b413d99076468f737e88fdfd66.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fae7f4612c548b1f72a964ddb291cd2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/424dd73a238dad799c9296e9ff829253.png)
![](https://img.xkw.com/dksih/QBM/2021/2/5/2651415694573568/2709632887603200/STEM/52453348-1c41-476f-bc39-73654ad0b82b.png?resizew=281)
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2021-04-28更新
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1142次组卷
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4卷引用:苏教版(2019) 必修第二册 过关斩将 第13章 13.2.4 平面与平面的位置关系 第1课时 两平面平行
苏教版(2019) 必修第二册 过关斩将 第13章 13.2.4 平面与平面的位置关系 第1课时 两平面平行(已下线)第03讲 空间直线、平面的平行 (高频考点—精讲)-2内蒙古鄂尔多斯市第一中学2020-2021学年高一上学期期末考试数学(理)试题(已下线)8.5.3 平面与平面平行(精练)-【题型分类归纳】2022-2023学年高一数学同步讲与练(人教A版2019必修第二册)