题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024313-12934.png)
A.m < a < b< n | B.a < m < n < b | C.a < m < b< n | D.m < a < n < b |
答案
解析
试题分析:类比“如果二次函数y=ax2+bx+c的图象与x轴有两个公共点,那么一元二次方程ax2+bx+c=0有两个不相等的实数根.”这句话,可以得出:若m、n(m<n)是关于x的方程
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024313-12934.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024313-26925.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024313-77316.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024313-59489.png)
可知:m < a < b< n,故选A.
核心考点
试题【“如果二次函数y=ax2+bx+c的图象与x轴有两个公共点,那么一元二次方程ax2+bx+c=0有两个不相等的实数根.”请根据你对这句话的理解,解决下面问题:若】;主要考察你对二次函数定义等知识点的理解。[详细]
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024303-96962.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024303-21238.png)
(1)求该抛物线的解析式;
(2)求点A关于直线
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024303-21238.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024303-72305.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024303-72305.png)
(3)点P是抛物线上一动点,过点P作y轴的平行线,交线段
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024303-27185.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024304-57364.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024252-91084.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024253-51211.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
(1)若花园的面积为192m2, 求x的值;
(2)若在P处有一棵树与墙CD,AD的距离分别是15m和6m,要将这棵树围在花园内(含边界,不考虑树的粗细),求花园面积S的最大值.
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024245-24026.jpg)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024204-66201.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024205-83254.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024205-79494.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024205-32349.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024205-85963.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024206-21653.png)
(1)若点D的横坐标为-5,求抛物线的函数表达式;
(2)若在第一象限的抛物线上有点P,使得以A,B,P为顶点的三角形与△ABC相似,求
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024205-83254.png)
(3)在(1)的条件下,设F为线段BD上一点(不含端点),连接AF,一动点M从点A出发,沿线段AF以每秒1个单位的速度运动到F,再沿线段FD以每秒2个单位的速度运动到D后停止. 当点F的坐标是多少时,点M在整个运动过程中用时最少?
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024206-97888.jpg)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024157-44324.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024158-15838.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024158-22335.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024158-50062.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024158-45642.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024159-27224.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024159-58670.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024159-31460.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024159-68048.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024159-12102.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024200-45039.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024200-68424.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024200-32463.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191019/20191019024200-14048.png)