名校
1 . 用反证法证明“设
,求证
”时,第一步的假设是______________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/127a0d8c1c7d15ed40ec4b8bca0ebdf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/485a2d99320384a0857b00ce9ab9e990.png)
您最近一年使用:0次
2020-03-20更新
|
475次组卷
|
7卷引用:陕西省渭南市韩城市西庄中学2020-2021学年高二下学期期中文科数学试题
2 . 先阅读下列题目的证法,再解决后面的问题.
已知
,且
,求证:
.
证明:构造函数
,
则
,
因为对一切
,恒有
,
所以
,
从而得
.
(1)若
,请由上述结论写出关于
的推广式;
(2)参考上述证法,请对你推广的结论加以证明.
已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2902a0c1309fe2d5490d6753d98d777.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53444e75341e1f40bf7d02c9ae6c47bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7397d7eab4d6f27a9bf0444c1b5ea889.png)
证明:构造函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bde9e414278cb72701ae87ba38bdab8.png)
则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bec845e92f934ce8c76dca49c872820.png)
因为对一切
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32a6e5b8aaed692d8be521e82df5a230.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e53c18d3b7ba956a1ec73418e6db9731.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/696b9008f29731ef9934398429e5b75f.png)
从而得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7397d7eab4d6f27a9bf0444c1b5ea889.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1b2d15f49b77537ea0efbd8b7fb6cc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09fc545b119b0b1c9e496e1c6ff9c25e.png)
(2)参考上述证法,请对你推广的结论加以证明.
您最近一年使用:0次
2018-06-24更新
|
247次组卷
|
13卷引用:陕西省澄城县2017-2018学年高二下学期期中考试数学(理)试题
陕西省澄城县2017-2018学年高二下学期期中考试数学(理)试题(已下线)2013-2014学年湘教版高二数学选修2-2基础达标6.1练习卷2015-2016学年安徽省六安一中高二下第一次段考文数学卷2016-2017学年江西省新余市高二上学期期末考试文数试卷河北省枣强中学2016-2017学年高二下学期期末考试数学(理)试题高中数学人教A版选修2-2 综合复习与测试 (4)黑龙江省海林市朝鲜族中学人教版高中数学选修1-2同步练习:第二章 推理与证明单元测评广东省佛山市第三中学2018-2019学年第二学期第一次段考高二理科数学试题安徽省马鞍山二中2018-2019学年高二下学期期中文科数学试题河南省南阳市第一中学2021-2022学年高二下学期第二次月考文科数学试题河南省郑州市第十九高级中学2020-2021学年高二下学期3月月考理科数学试题上海市浦东新区川沙中学2015-2016学年高一上学期期中数学试题沪教版(2020) 必修第一册 达标检测 第二章 章测试
解题方法
3 . 如图,在直三棱柱
中,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/29/a3acc036-e01d-48a6-8ef3-1a66c959410a.jpg?resizew=126)
(1)证明:
平面
;
(2)若
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36cf3bff56a7f4ab6c0008e90823025d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/289d7a880379d6060065c829b45b0ed6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/29/a3acc036-e01d-48a6-8ef3-1a66c959410a.jpg?resizew=126)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d85c8d87197c9ffad619eb3912e1b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6610370a5aefaf45fdb579521484e3b5.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6e937690538483bca282ff6831772b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3bdeec91171e6d0c5247f199ffd7c63.png)
您最近一年使用:0次
2018-03-26更新
|
803次组卷
|
4卷引用:陕西省渭南市蒲城中学2023-2024学年高二上学期9月开学考试数学试题
解题方法
4 . 在平面直角坐标系
中,椭圆
的右顶点和上顶点分别为
,点
是直线
上的动点,设直线
斜率分别为
.
(1)求椭圆
的离心率;
(2)求证:
为定值;
(3)若直线
与椭圆的另一个交点分别为
,试判断直线
与直线
的位置关系.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7795aec93c2c7ac2fd93e6747ca6516c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb4402aeb853b22f20992156957ef0fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b87609b100b8d39b52e25ef1bee9b772.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/790ef3382b1c731f2885eecfd92c2a86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90963760acac7bfad3ae03088c6c80b0.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4757181824e15e0f21e5bdd55448783.png)
(3)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/790ef3382b1c731f2885eecfd92c2a86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39acab3cfb59bfc9591371721ab01d93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
您最近一年使用:0次
名校
5 . 如图,在四棱锥P﹣ABCD中,
⊥底面
,
,
,
,点E为棱
的中点.
(1)证明:
;
(2)求直线
与平面
所成角的正弦值;
(3)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9060f03b9ee41d70d135b1e1a8902ce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee8ef58be8708144272538ee427fb92c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/860850e8013f9399382f9344112725cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/8/387f9745-e10a-46be-b422-74d0b62b660e.png?resizew=166)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c38bbe49284a2ceab26001ced8cfd56.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fba0dd982b283611f4d01be499546af9.png)
您最近一年使用:0次
2024-01-05更新
|
480次组卷
|
3卷引用:陕西省渭南市渭南中学2023-2024学年高二上学期期末质量调研数学试题
解题方法
6 . 已知椭圆
的离心率为
,右焦点为
,斜率不为0的直线l与C交于A,B两点.
(1)求椭圆C的方程;
(2)若直线l经过点
(点A在点B,Q之间),直线BF与C的另一个交点为D,求证:点A,D关于x轴对称.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad523e69a1bf925e73a22900b9855df2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2ba2238d6afe0187534155dd9ac48c6.png)
(1)求椭圆C的方程;
(2)若直线l经过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8d419a3c588616c8e9765cd4bbb6190.png)
您最近一年使用:0次
名校
7 . 如图,在三棱锥
中,
为正三角形,平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/12/28127681-d04b-4d6c-bf58-2852053953be.png?resizew=168)
(1)求证:
;
(2)若
是
的中点,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4357d5744046d4d44abb09e1ee35fcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17580410bf63dba4fe164265afaac4cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e9c515dc5337d5ed8afe3f81b68c57a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/12/28127681-d04b-4d6c-bf58-2852053953be.png?resizew=168)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d900531973c546625694146fa1509ab9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
您最近一年使用:0次
2023-12-11更新
|
1479次组卷
|
7卷引用:陕西省渭南市高级中学2023-2024学年高二上学期12月月考数学试题
陕西省渭南市高级中学2023-2024学年高二上学期12月月考数学试题云南省沧源佤族自治县民族中学2021~2022学年高二上学期期末考试数学试题福建省龙岩市第一中学2023-2024学年高二上学期第三次月考数学试题(已下线)高二上学期数学期末模拟卷(一)-2023-2024学年高二数学同步精品课堂(北师大版2019选择性必修第一册)云南省昆明市第三中学2023-2024学年高二下学期第一次综合测试数学试卷6.3 空间向量的应用 (5)江西省宜春市丰城市第九中学2023-2024学年高二上学期期末考试数学试题
名校
解题方法
8 . 如图,过点
的椭圆
的离心率为
,椭圆与
轴交于点
,过点
的直线
与椭圆交于另一点
,并与
轴交于点
,直线
与直线
交于点
;
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/28/c1612ca3-6697-44a0-ba68-fb3bf8bb6cc2.png?resizew=174)
(1)当直线
过椭圆右焦点时,求
点的坐标;
(2)当点
异于点
时,求证:
为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52f6dd0159f0fe46dbc3f4e493f8d3e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48da128547c4cf9745e8e4b99988a3db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/860884c0017c8bceb5b0edff796c144f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf1ee6720a96e47c7e509941d53dc7a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/28/c1612ca3-6697-44a0-ba68-fb3bf8bb6cc2.png?resizew=174)
(1)当直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
(2)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a5215b714cde3ed7790b3ed4f6711c3.png)
您最近一年使用:0次
解题方法
9 . 设椭圆的方程为
(
),离心率为
,过焦点且垂直于
轴的直线交椭圆于A,
两点,
.
(1)求该椭圆的标准方程;
(2)设动点
满足
,其中
,
是椭圆上的点,直线
与
的斜率之积为
,求证:
为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7aea48c44781a844b5c19191f70f61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a0c4c098615c6bc7e6dcf72e5b5201a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae5a64bcb77f5f64e4af6930c249a270.png)
(1)求该椭圆的标准方程;
(2)设动点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7775aa57ca0e62216f3039ed88dceed0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/150183f6a054c9a47ab8655046a0f8f7.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/aaf3369e0ea90e8d5cf4b6b3c45c0fd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88e9f7d1272b7344346b58b660aa260a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3389f53711264b0acba3ba6019f8b908.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4818b8e315a1c68c788e21a275966bb7.png)
您最近一年使用:0次
名校
解题方法
10 . 已知
是抛物线
:
上一点,且
到
的焦点的距离为
.
(1)求抛物线
的方程及点
的坐标;
(2)已知直线
与抛物线
相交于A,B两点,
为坐标原点.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35b44f2573d4a0537783d254d965c9a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3764ba3aa0a241787f4661026bb14053.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/533a7b702ada1dd80123e4041271d521.png)
(1)求抛物线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
(2)已知直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/026808536f6b6d265c778e23836fbf13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3825ccc273ef9a672a606432d165b866.png)
您最近一年使用:0次
2023-11-18更新
|
762次组卷
|
3卷引用:陕西省渭南市高级中学2023-2024学年高二上学期12月月考数学试题