题目
题型:不详难度:来源:
A
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175050-49141.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175051-97884.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175051-96292.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175051-25268.png)
答案
解析
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175051-86812.png)
则椭圆中心到其准线距离可得.
解答:解:依题意可知b=1,a=2
∴c=
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175051-27407.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175052-78802.png)
∴准线方程为y=±
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175051-86812.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175052-88060.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175051-86812.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175052-88060.png)
∴椭圆中心到其准线距离是
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175052-88060.png)
故选D
点评:本题主要考查了椭圆的简单性质.属基础题.
核心考点
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175044-56207.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175045-23123.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175045-16551.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175045-68763.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175028-65103.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175028-73430.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175028-76446.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175029-61332.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175029-79778.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175029-18981.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175029-40677.jpg)
(1)试求椭圆的方程;
(2)过
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175029-10778.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175029-66903.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175020-52167.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175021-19216.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175021-22058.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175021-50354.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175021-10212.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175022-90751.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175022-19705.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175022-61393.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175022-79440.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175023-64943.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175023-56889.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175023-39175.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175023-87858.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175024-38537.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175014-14250.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175015-91490.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175015-95199.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175015-47771.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175015-53783.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175015-59402.png)
A. 1 | B. 2 | C.![]() | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175009-91005.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191023/20191023175009-85232.gif)
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