已知二次函数y=ax2+bx+c的图象经过点A(1,0).
(1)当b=2,c=﹣3时,求二次函数的解析式及二次函数最小值;
(2)二次函数的图象经过点B(m,e),C(3﹣m,e)且对任意实数x,函数值y都不小于
﹣
.
①求此时二次函数的解析式;
②若次函数与y轴交于点D,在对称轴上存在一点P,使得PA+PD有最小值,求点P坐标及PA+PD的最小值.
(1)当b=2,c=﹣3时,求二次函数的解析式及二次函数最小值;
(2)二次函数的图象经过点B(m,e),C(3﹣m,e)且对任意实数x,函数值y都不小于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afd5daa9a0b9a14a4a44b02bae65b586.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
①求此时二次函数的解析式;
②若次函数与y轴交于点D,在对称轴上存在一点P,使得PA+PD有最小值,求点P坐标及PA+PD的最小值.
19-20九年级上·福建厦门·期中 查看更多[2]
福建省厦门市思明区松柏中学2019-2020学年九年级上学期期中数学试题(已下线)专题2.40 二次函数背景下周长最值问题(专项练习)-2021-2022学年九年级数学下册基础知识专项讲练(北师大版)
更新时间:2020-01-26 14:09:16
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