解题方法
1 . 阅读下面题目及其解答过程.
如图,在直三棱柱
中,
,D,E分别为BC,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/24/d053b157-0829-465a-b6dc-3ea9c85cb713.png?resizew=138)
(1)求证:
平面
;
(2)求证:
.
解:(1)取
的中点F,连接EF,FC,如图所示.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/24/0a94878a-2f4f-4376-980a-eaccd4e4ed9b.png?resizew=139)
在
中,E,F分别为
,
的中点,
所以
,
.
由题意知,四边形
为 ① .
因为D为BC的中点,所以
,
.
所以
,
.
所以四边形DCFE为平行四边形,
所以
.
又 ② ,
平面
,
所以,
平面
.
(2)因为
为直三棱柱,所以
平面ABC.
又
平面ABC,所以 ③ .
因为
,且
,所以 ④ .
又
平面
,所以
.
因为 ⑤ ,所以
.
以上题目的解答过程中,设置了①~⑤五个空格,如下的表格中为每个空格给出了两个选项,其中只有一个符合逻辑推理.请选出符合逻辑推理的选项,并填写在答题卡的指定位置(只需填写“A”或“B”).
如图,在直三棱柱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/24/d053b157-0829-465a-b6dc-3ea9c85cb713.png?resizew=138)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9874eca4abea481fa84eb772a920f9c7.png)
解:(1)取
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/24/0a94878a-2f4f-4376-980a-eaccd4e4ed9b.png?resizew=139)
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4310db23fc79936c7182361e652bab1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac03bd962f6fbfecb16b558f3c374784.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcfbf154e19cbd0580d58ccc9bac077c.png)
由题意知,四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f96c673a2381f118ea2d3efc0bca1f3.png)
因为D为BC的中点,所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd1ab54c55e934d0263f0aa33acb6116.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38d0463b6e3d27b5cfc1df0e6c14fbef.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70099a8a0e7cff25485a63e8811a6aab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aeeadcae4a2964c73187962918724ae7.png)
所以四边形DCFE为平行四边形,
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dced11455b3e31a9090915f80a046fa3.png)
又 ② ,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e3ffd599e4fb57893b141bad96c66b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
所以,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
(2)因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1ecf072589c0f901d92f6bda111d841.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be509ef5101aae24609ff9941cb246fc.png)
因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83499936f532ddce9068dd1ff8eb2b01.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e3ffd599e4fb57893b141bad96c66b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9f76925ed99b7172956319974258a9b.png)
因为 ⑤ ,所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9874eca4abea481fa84eb772a920f9c7.png)
以上题目的解答过程中,设置了①~⑤五个空格,如下的表格中为每个空格给出了两个选项,其中只有一个符合逻辑推理.请选出符合逻辑推理的选项,并填写在答题卡的指定位置(只需填写“A”或“B”).
空格序号 | 选项 |
① | A.矩形 B.梯形 |
② | A.![]() ![]() ![]() ![]() |
③ | A.![]() ![]() |
④ | A.![]() ![]() ![]() ![]() |
⑤ | A.![]() ![]() |
您最近一年使用:0次
解题方法
2 . 如图,在正方体
中,
是正方形ABCD及其内部的点构成的集合.给出下列三个结论:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/25/4960be11-8404-4793-b39d-60d44fb9a902.png?resizew=158)
①
,
;
②
,
;
③
,
与
不垂直.
其中所有正确结论的序号是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cffa35373ec4e4684107b42adb7a5161.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/25/4960be11-8404-4793-b39d-60d44fb9a902.png?resizew=158)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d0aa37f3d7918b9b55c4eefc76ae421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de9332e9e07d322d6ca7655c1203edd3.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54d3f205531cb8f3a50b1e1326d13387.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2985949e7810abec5a2d4994f81c683a.png)
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d0aa37f3d7918b9b55c4eefc76ae421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d0ff310aabd2282b539537ebed3f788.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
其中所有正确结论的序号是
您最近一年使用:0次
解题方法
3 . 正四棱锥
中,8条棱长均相等,且
,则此正四棱锥的体积为_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
您最近一年使用:0次
解题方法
4 . 如图,在三棱锥P-ABC中,PA⊥底面ABC,
,则这个三棱锥的四个面中,是直角三角形的个数有_____ 个.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
您最近一年使用:0次
2022-06-20更新
|
1316次组卷
|
4卷引用:广西普通高中2021-2022学年高二6月学业水平考试数学试题
广西普通高中2021-2022学年高二6月学业水平考试数学试题专题07A立体几何选择填空题(已下线)第一章 点线面位置关系 专题二 空间垂直关系的判定与证明 微点2 空间直线垂直的判定与证明综合训练【基础版】(已下线)8.6.2 直线与平面垂直【第一练】“上好三节课,做好三套题“高中数学素养晋级之路
解题方法
5 . 直棱柱
中,
,点
分别是线段
的中点,则异面直线
与
所成角的正切值是_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7e02ca8b54de5da34fbf83f8e8c99d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bce3d91ca23b86d8c6625f2632e437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1857eadd6b23a87a1a5b4ffff584efd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
您最近一年使用:0次
解题方法
6 . 如图,在
中,
,
是斜边
的中点,将
沿直线
翻折,若在翻折过程中存在某个位置,使得
,则
的取值范围是_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb3944427f17f33d72fdc2277390be94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661ff55b5ebbadfb600989af3cfce2fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/324aae9536a57bcaf320795715f20b75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://img.xkw.com/dksih/QBM/2020/12/29/2624712283963392/2625505506770944/STEM/3aafcbe5-b968-4049-90bd-35afee5b0583.png?resizew=521)
您最近一年使用:0次
12-13高二上·浙江杭州·阶段练习
名校
解题方法
7 . 过
所在平面
外一点
,作
,垂足为
,连接
,
,
,若
,则点
是
的______ 心.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59169f91ebc758ba6e73fc99fcfaab15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30fc65a72853bd8ac1ad0828270d3baf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
2023-10-22更新
|
306次组卷
|
5卷引用:四川省南充市2015-2016学年高一年下学期学业水平评估考试数学
四川省南充市2015-2016学年高一年下学期学业水平评估考试数学(已下线)2012-2013学年浙江省富阳场口中学高二9月质量检测文科数学试卷广东省广东实验中学2019-2020学年高二上学期开学摸底考试数学试题上海市七宝中学2023-2024学年高二上学期10月月考数学试题上海市七宝中学2023-2024学年高二上学期9月月考数学试题
解题方法
8 . 阅读下面题目及其证明过程,并回答问题.
如图,在三棱锥
中,
底面
,
,
,
分别是棱
,
的中点.
![](https://img.xkw.com/dksih/QBM/2020/11/10/2590155875131392/2590586443956224/STEM/59e96d8fb6364a7a9a0c2415e5ced222.png?resizew=229)
(1)求证:
平面
;
(2)求证:
.
解答:(1)证明:在
中,
因为
,
分别是
,
的中点,
所以
.
因为
平面
,
平面
,
所以
平面
.
(2)证明:在三棱锥
中,
因为
底面
,
平面
,
所以______.
因为
,且
,
所以______.
因为
平面
,
所以______.
由(1)知
,
所以
.
问题1:在(1)的证明过程中,证明的思路是先证______,再证______.
问题2:在(2)的证明过程中,设置了三个空格.请从下面给出的四个选项中,为每一个空格选择一个正确的选项,以补全证明过程.
①
;②
;③
平面
;④
.
如图,在三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.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/2a30f3a8b673cc28bd90c50cf1a35281.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/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/2020/11/10/2590155875131392/2590586443956224/STEM/59e96d8fb6364a7a9a0c2415e5ced222.png?resizew=229)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc90fee532e50d319081d571410421.png)
解答:(1)证明:在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c025ee3317be1099b7bf03a11e37ed4.png)
因为
![](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/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f6c1984e2068203465b10ea4ead7916.png)
因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/871502ee0c5d1414cfe81e8409b62d76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c9fe3c7e943c3beb7f4bbf345822064.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)证明:在三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8690d88536618e3f993dae41a3de66a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
所以______.
因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34baf7aadc048e75e776b80eea5b62b5.png)
所以______.
因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c9fe3c7e943c3beb7f4bbf345822064.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
所以______.
由(1)知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f6c1984e2068203465b10ea4ead7916.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc90fee532e50d319081d571410421.png)
问题1:在(1)的证明过程中,证明的思路是先证______,再证______.
问题2:在(2)的证明过程中,设置了三个空格.请从下面给出的四个选项中,为每一个空格选择一个正确的选项,以补全证明过程.
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a15a004f7d47ed595f063e60075223a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0d9ef979b9f27a28cbda6923e888ccc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da48240e7fc3248f773ac1500c15ec14.png)
您最近一年使用:0次