23-24高二上·上海·课后作业
1 . 请指出下列各题用数学归纳法证明过程中的错误.
(1)设
为正整数,求证:
.
证明:假设当
(
为正整数)时等式成立,即有
.
那么当
时,就有![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b265260b1c40af006ba6f66a11ed576.png)
.因此,对于任何正整数
等式都成立.
(2)设
为正整数,求证:
.
证明:①当
时,左边
,右边
,等式成立.
②假设当
(
,
为正整数)时,等式成立,即有
,
那么当
时,由等比数列求和公式,就有
,等式也成立.
根据(1)和(2),由数学归纳法可以断定
对任何正整数
都成立.
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b502d9c57239d9f42fdf849878018061.png)
证明:假设当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef7ca2b3e8061384501f668e59696a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d8963d68c930f5b28cc8b92c43d469b.png)
那么当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63ba21f3d0cfc86d40e2e06446623ce0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b265260b1c40af006ba6f66a11ed576.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced66f7e147b6276e1ce9e2b67510141.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8883d7d43d3f61a771d16537c52ac451.png)
证明:①当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c87b351f16728b0023fd63678f8103c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90bae886c8ab958aa4c693bf8e0627d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90bae886c8ab958aa4c693bf8e0627d.png)
②假设当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef7ca2b3e8061384501f668e59696a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2397df3279607612ea3cbef101ee0bf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a439aebc27b99718f09e1dff2649482f.png)
那么当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63ba21f3d0cfc86d40e2e06446623ce0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b838d781d5ce98ddcc08af86c1f27ae.png)
根据(1)和(2),由数学归纳法可以断定
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8883d7d43d3f61a771d16537c52ac451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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2022高一·全国·专题练习
2 . 如图所示,在四棱锥P﹣ABCD中,底面ABCD是∠DAB=60°且边长为a的菱形,侧面PAD为正三角形,其所在的平面垂直于底面ABCD.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/15/05656903-75b3-4bdf-89d9-4173c16734a7.png?resizew=202)
(1)若G为AD边的中点,求证:BG⊥平面PAD;
(2)求证:AD⊥PB;
(3)求二面角A﹣BC﹣P的大小;
(4)若E为BC边的中点,能否在棱PC上找一点F,使得平面DEF⊥平面ABCD?并证明你的结论.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/15/05656903-75b3-4bdf-89d9-4173c16734a7.png?resizew=202)
(1)若G为AD边的中点,求证:BG⊥平面PAD;
(2)求证:AD⊥PB;
(3)求二面角A﹣BC﹣P的大小;
(4)若E为BC边的中点,能否在棱PC上找一点F,使得平面DEF⊥平面ABCD?并证明你的结论.
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2022-06-14更新
|
937次组卷
|
3卷引用:10.4 平面与平面间的位置关系(第2课时)(九大题型)(分层练习)-2023-2024学年高二数学同步精品课堂(沪教版2020必修第三册)
(已下线)10.4 平面与平面间的位置关系(第2课时)(九大题型)(分层练习)-2023-2024学年高二数学同步精品课堂(沪教版2020必修第三册)(已下线)8.6.2 空间角与空间距离(精练)-2022-2023学年高一数学一隅三反系列(人教A版2019必修第二册)(已下线)专题25 二面角相关问题训练-【重难点突破】2021-2022学年高一数学常考题专练(人教A版2019必修第二册)
名校
解题方法
3 . 长方体
中,
,
.点
为
中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/1/a5b069ed-227e-4938-9540-a82305a05945.png?resizew=158)
(1)求证:
平面
;
(2)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/480f4df0a32a910db7d39695ffd86665.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/1/a5b069ed-227e-4938-9540-a82305a05945.png?resizew=158)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4890e58791814622b87c4d60ea971f54.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679748eab882a6be0fefd2cc300349a4.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f11f1840eb8b17e7b07c3fe7e987a9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/657dffbd3623b705f871878fbd9df57e.png)
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2023-12-01更新
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276次组卷
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3卷引用:3.4.1 判断空间直线、平面的位置关系(六大题型)(分层练习)-2023-2024学年高二数学同步精品课堂(沪教版2020选择性必修第一册)
(已下线)3.4.1 判断空间直线、平面的位置关系(六大题型)(分层练习)-2023-2024学年高二数学同步精品课堂(沪教版2020选择性必修第一册)广东省江门市台山市华侨中学2023-2024学年高二上学期期中数学试题(已下线)第6章 空间向量与立体几何 章末题型归纳总结-【帮课堂】2023-2024学年高二数学同步学与练(苏教版2019选择性必修第二册)
4 . 设X是一个随机变量,c是常数.求证:X+c的方差与X的方差相等.
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23-24高二上·上海·课后作业
解题方法
5 . 如图,在直三棱柱
中,
,
,棱
,点
、
分别是
、
的中点.建立适当的空间直角坐标系,解决如下问题:
(1)求
的模;
(2)求
;
(3)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae445b17e686495b7ef5783c83c96410.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a3cc9cccfb4c260dac05f4ed57e8c10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a4acc5d21a7490e6bed2453cc5147c1.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/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a696a182fff038a86b2bbe8ca099442.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/14/4a12667b-b2bc-4aea-b5c7-4068e55ddf8f.png?resizew=105)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/350f162ee9aa08f4c9779481a5ef1025.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe8732e96e02aa9a706af3f0dc4c6796.png)
(3)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24b201f1e798eb74963b98f2b0da4132.png)
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6 . 求证:椭圆
与椭圆
的四个交点共圆.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6533a2123bcaa8c7dcd36d5e3f37700f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcfe5374dd26ea48089dd73dfa669ae1.png)
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23-24高二上·上海·课后作业
解题方法
7 . 已知数列
的前
项和为
,求证:数列
是等差数列.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82c662d8f38a824e3c9c2e26a7828a9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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23-24高二上·上海·课后作业
8 . 在空间四面体
中,
,
.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70734a8e672376bb0bd1522e229f86a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b757f0c42ae5c9a2d6a4b19e5877b27.png)
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9 . 已知直线
的方程为
.求证:
(1)无论
取何值时,
都经过一个确定的点
;
(2)无论
取何值时,对于
上任意一点
,向量
均与向量
垂直.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02e909a7bc31ef2f35e4be4d80d28698.png)
(1)无论
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
(2)无论
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3722488cf68b05c22d3e6c0b4de6991.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbac9b04118d36bbffab6ded0c964fb.png)
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