题目
题型:高考真题难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084041-66523.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084041-85961.png)
核心考点
举一反三
①失事船的移动路径可视为抛物线
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084032-65961.png)
②定位后救援船即刻沿直线匀速前往救援;
③救援船出发t小时后,失事船所在位置的横坐标为7t。
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084032-80191.png)
(2)问救援船的时速至少是多少海里才能追上失事船?
过抛物线y2=4x上一点A(1,2)作抛物线的切线,分别交x轴于点B,交y轴于点D,点C(异于点A)在抛物线上,点E在线段AC上,满足
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084019-68668.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084019-86482.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084019-95844.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084020-29800.png)
λ1+λ2=1,线段CD与EF交于点P.
(1)设
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084020-17865.png)
(2)当点C在抛物线上移动时,求点P的轨迹方程.
![](http://img.shitiku.com.cn/uploads/allimg/20191024/20191024084020-27131.png)