题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013209-38173.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013209-53050.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013210-51763.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013210-91562.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013210-30200.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013210-22664.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013209-53050.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013210-22664.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013209-53050.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013210-65167.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013211-42531.png)
(Ⅰ)求点
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013211-42531.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013211-72766.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013211-72766.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013211-58811.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013211-20611.png)
解析
试题分析:(1) 根据线段垂直平分线的定义所以点P到F的距离等于到直线
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013209-53050.png)
所以,点P的轨迹是以F为焦点,
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013209-53050.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013212-73146.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013212-34918.png)
所以所求的轨迹方程为
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013211-20611.png)
(2) 设
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013212-40756.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013212-15150.png)
代入到抛物线方程整理得 则
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013212-73984.png)
根据韦达定理
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013213-52573.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013213-33936.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013213-45616.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013213-71755.png)
即
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013214-93996.png)
显然,不论
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013214-11493.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013214-66722.png)
点评:求轨迹方程的方法较多,首先应考虑定义法,即利用常见曲线的定义,从条件出发确定几何元素。直线与圆锥曲线的位置关系问题,韦达定理常常用到。
核心考点
试题【(满分12分)已知点,直线: 交轴于点,点是上的动点,过点垂直于的直线与线段的垂直平分线交于点.(Ⅰ)求点的轨迹的方程;(Ⅱ)若 A、B为轨迹上的两个动点,且 】;主要考察你对曲线与方程的应用等知识点的理解。[详细]
举一反三
设点P是圆x2 +y2 =4上任意一点,由点P向x轴作垂线PP0,垂足为Po,且
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013156-87910.png)
(Ⅰ)求点M的轨迹C的方程;
(Ⅱ)设直线
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013157-57359.png)
(1)若直线OA,AB,OB的斜率成等比数列,求实数m的取值范围;
(2)若以AB为直径的圆过曲线C与x轴正半轴的交点Q,求证:直线
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013157-57359.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013148-31986.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013148-91278.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013149-44694.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013149-93874.png)
A.![]() | B.![]() | C.![]() | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013139-37603.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013139-73968.png)
(1)若|AB|=8,求抛物线
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013139-37918.png)
(2)设C为抛物线弧AB上的动点(不包括A,B两点),求
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013139-79659.png)
(3)设P是抛物线
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013139-37918.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013130-72563.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013131-76091.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013131-27621.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013131-13558.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013131-27621.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013131-89578.png)
A.![]() | B.![]() | C.![]() | D.![]() |
已知椭圆
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013118-14423.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013118-84919.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013119-44634.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013119-81244.png)
(I)求椭圆
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013118-14423.png)
(II)直线
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013119-83985.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013118-14423.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013119-57116.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013119-64156.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013120-54158.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013120-25102.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013120-66325.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013120-54158.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013120-95612.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013121-65446.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013120-54158.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013121-92318.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191026/20191026013121-14661.png)
最新试题
- 1下列是我国古代四大名著中的有关内容的句子,请任选一句,根据名著中的内容扩展成一段故事简介。(60字以内)①败走华容道 ②
- 2有人学习了《愚公移山》的故事后,认为愚公真“愚”,为什么移山不用炸药炸,用挖土机挖,用汽车运呢?这种观点主要错在否认了[
- 3化学世界千变万化,请写出下列反应的文字表达式.(1)碳酸氢铵受热分解______;(2)二氧化碳通入水中______;(
- 4When the TV viewer turns on his set, what sort of programs d
- 5你的性别是_________,体内的主要性激素是______________,它是由________分泌的。
- 6产生胆汁的器官是 [ ]A.肝脏 B.胰腺 C.小肠 D.大肠
- 7将一个带电量为1×10-6C的负电荷从电场中的A点移到B点,克服电场力做功3×10-6J.从B点移到C点,电场力做功5×
- 8郭沫若说:“一片甲骨惊天下。”主要因为甲骨文是[ ]A.商代的文字B.刻在龟甲或兽骨上的文字C.目前我国发现最早
- 9下列词语中加点字注音全对的一项是( )(3分)A.锦幛(zhàng) 着落(zhuó)禁锢(jìn)遍稽群籍(jí)B
- 10_________ with the size of the whole earth, the biggest ocea
热门考点
- 1根据所给信息,在横线处填上相应物质的名称或化学式:(1)地球表面约71%被它覆盖,常用作化学实验的溶剂的物质是 ____
- 2如图,在□ABCD中,E是BC边上一点,且BE:EC=2:3,AE交BD于点F,则=( )。
- 3设立锦衣卫特务机构的是下列哪位皇帝[ ]A、宋太祖B、宋太宗C、明太祖D、明成祖
- 4 They will lose the game _______ they try their best.A.unles
- 5如图所示,在距水平地面高为0.4 m处,水平固定一根长直光滑杆,杆上P处固定一定滑轮(大小不计),滑轮可绕水平轴无摩擦转
- 6《那树》体裁是___________ ,作者是_________ ,他是___________ 当代作家。
- 7阅读下面的文字,完成小题。树欲静而风不止心 远嵇康,字叔夜。谯国铚县(今安徽濉溪)人。作为西晋时的文学家、哲学家与音乐家
- 8请阅读《礼记.礼运》中的两段文字,回答问题。材料一:大道之行也,天下为公。选贤与能,讲信修睦。故人不独亲其亲,不独子其子
- 9句型转换。1. What else did you do? (改为同义句) _____ _____ _____ d
- 10全世界每年有成百上千人由于吃毒蘑菇而身亡,其中鹅膏草碱就是一种毒菇的毒素,它是一种环状八肽。若20种氨基酸的平均分子量为