1 . 设函数
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/3/069751d0-d183-4db6-bda1-d936ef131f93.png?resizew=170)
(1)在平面直角坐标系中画出它的图象;
(2)解不等式
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24438824d475f58a8ddcc0e05b599468.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/3/069751d0-d183-4db6-bda1-d936ef131f93.png?resizew=170)
(1)在平面直角坐标系中画出它的图象;
(2)解不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0dd18467feea8eb478f4669a32c2d57.png)
您最近一年使用:0次
解题方法
2 . (1)解不等式
;
(2)对于题目:已知
,
,且
,求
最小值.
同学甲的解法:因为
,
,所以
,
,从而:
.
所以
的最小值为8.
同学乙的解法:因为
,
,
所以
.
所以
的最小值为
.
①请对两位同学的解法正确性作出评价;
②为巩固学习效果,老师布置了另外一道题,请你解决:
已知
,
,且
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b75cc5360e0e54cde5e73ffbea959790.png)
(2)对于题目:已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b140e221ddf537b8964fff8557cca0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de8610232c77741a37463feba1a66c94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d73552080b72be89317eb60e9bef76c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27a0d4c12a65a54c29f1ef8e2601d29d.png)
同学甲的解法:因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b140e221ddf537b8964fff8557cca0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de8610232c77741a37463feba1a66c94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4251548d5b6df7d28599be1002f02ad5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba107edb7565f1f294137d2b70548ce3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5acc0d2031d4d6ede3838732b4b90fbf.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
同学乙的解法:因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b140e221ddf537b8964fff8557cca0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de8610232c77741a37463feba1a66c94.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ff78ba3e74c1fa1f1abdb83969c3277.png)
所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ec978eb43bc4f9e7df83b0d0195dcda.png)
①请对两位同学的解法正确性作出评价;
②为巩固学习效果,老师布置了另外一道题,请你解决:
已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67ca5fd57c2c2fcc3c7a574fdd1467d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/def2a209038816cc74a1bafb8f390598.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/add21924d10481916191cad9cde56b50.png)
您最近一年使用:0次