2016高二·全国·课后作业
解题方法
1 . 如图所示,在
中,
,其中
,
,
分别为角
,
,
的对边,在四面体
中,
,
,
,
分别表示
,
,
,
的面积,
,
,
依次表示面
,面
,面
与底面
所成二面角的大小.写出对四面体性质的猜想,并证明你的结论
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42be770d7c89c564928a9c5bad054c50.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a351136b18bc7d3bd5122332772ab23b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6899bf9cadae2ccdb14cbc87d4f280ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2205cffebf8c4d5f81d15ed7b85c8936.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c025ee3317be1099b7bf03a11e37ed4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ac779b70bd71ae3a77721efb04c62b0.png)
![](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/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f435efcc7869eec21bdba1ed81dc3f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b34cf4760da098099493d4627dacb878.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/b5acbcbb-5e80-45de-80c5-b993f1f55a22.png?resizew=277)
您最近一年使用:0次
2020-06-10更新
|
187次组卷
|
7卷引用:安徽省滁州市定远县民族中学2017-2018学年高二下学期期末考试数学(理)试题
安徽省滁州市定远县民族中学2017-2018学年高二下学期期末考试数学(理)试题安徽省滁州市定远县育才学校2019-2020学年高二下学期5月月考数学(理)试题安徽省滁州市民办高中2019-2020学年高二下学期期末数学(理)试题(已下线)同步君人教A版选修1-2第二章 2.1.1合情推理(已下线)同步君人教A版选修2-2第二章2.1.1合情推理高中数学人教版 选修2-2(理科) 第二章推理与证明 2.1.1合情推理高中数学人教版 选修1-2(文科) 第二章 推理与证明 2.1.1 合情推理
2 . 如图1,已知
中,
,点
在斜边
上的射影为点
.
![](https://img.xkw.com/dksih/QBM/2018/7/8/1984043695022080/1985696665255936/STEM/5f681ef49f6b4dccac078de8f9fda743.png?resizew=400)
(Ⅰ)求证:
;
(Ⅱ)如图2,已知三棱锥
中,侧棱
,
,
两两互相垂直,点
在底面
内的射影为点
.类比(Ⅰ)中的结论,猜想三棱锥
中
与
,
,
的关系,并证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53502463cc76201000e02df314e58769.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83640592853a53872d7af69c0cffc1bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://img.xkw.com/dksih/QBM/2018/7/8/1984043695022080/1985696665255936/STEM/5f681ef49f6b4dccac078de8f9fda743.png?resizew=400)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/520306e216b3af1fe08c1762e200610f.png)
(Ⅱ)如图2,已知三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.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/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35d58f9019097bd05037aefd5c322916.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)
您最近一年使用:0次
2018-07-10更新
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540次组卷
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5卷引用:【全国市级联考】安徽省蚌埠市2017-2018学年高二下学期期末考试数学(理)试题
【全国市级联考】安徽省蚌埠市2017-2018学年高二下学期期末考试数学(理)试题【全国市级联考】安徽省蚌埠市2017-2018学年高二下学期期末考试数学(文)试题【全国百强校】湖南省湘潭县一中、双峰一中、邵东一中、永州四中2018-2019学年高二下学期优生联考数学试题(已下线)2.1.1 合情推理-2020-2021学年高二数学(理)课时同步练(人教A版选修2-2)河北省衡水市第十三中学2019届高三质检(四)文科数学试题
3 . 先观察不等式
(
、
、
、![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
)的证明过程:
设平面向量
,
,则
,
,
.
∵
,
∴
,
∴
,
再类比证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcb5838a28febd791d0a52a6d788554b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/160daec0ad9ccc242f3e259eb4d61ef6.png)
设平面向量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa504004300e52762153d5647126eb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7bb3087f2503659cdfc234c5b73785c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8105c72ea62188b6bf9f96b2048469a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef025990a50724087c6324c79d806e1b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17c41f0b66fd9b652fbba77938b68aa3.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e21c4d082a3dfbd30c2f9d379a519a36.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdd9ca3dfd5c3775273dc01d6fec1daf.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/843b0787ac55039e0afea11924b2c3af.png)
再类比证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73190531835c7af7c18096811c081d1e.png)
您最近一年使用:0次