解题方法
1 . 数学家Dandelin用来证明一个平面截圆柱得到的截口曲线是椭圆的模型(称为“Dandelin双球”).如图,在圆柱内放两个大小相同的小球
,使得两球球面分别与圆柱侧面相切于以
为直径且平行于圆柱底面的圆
和
,两球球面与斜截面分别相切于点
,点
为斜截面边缘上的动点,则这个斜截面是椭圆.若图中球的半径为3,球心距离
,则所得椭圆的离心率是___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d096cd7bd8a5a2219fd7dd166bbb8460.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3956369191d0383bdb8786134da7dd9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c4f6f74444b2b7947fc6e35c8d62322.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/149bd0effc0c1277b9069c59c3566f07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/647af54e46e22ea0160071ca6eacb1a5.png)
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2022-11-16更新
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4卷引用:江西省名校联盟2022-2023学年高二上学期期中联考数学试题
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2 . 已知斜率为1的直线
与椭圆
交于
,
两点,且线段
的中点为
,椭圆
的上顶点为
.
(1)求椭圆
的离心率;
(2)设直线
与椭圆
交于
两点,若直线
与
的斜率之和为2,证明:
过定点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad523e69a1bf925e73a22900b9855df2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3860d9fa9fe43eeecea30202d880f2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cf7358675528bc6342a378563a197a8.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)设直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23a44baceab9e1d74f6ca53aea8c4d72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7785afeeaf274892253d04b4f693b367.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13dea1bd3d0dd84b8b6f6ff634c5600c.png)
您最近一年使用:0次
2019-06-15更新
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1130次组卷
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6卷引用:江西省宜春市高安市高安中学2019-2020学年高二上学期期末数学(理)试题