搜题请搜索小程序“爱下问搜题”
问题 填空题
若f（x）是偶函数，其定义域为R且在[0，+∞）上是减函数，则f（-
3
4
）与f（a2-a+1）的大小关系是______．
答案

∵a2-a+1=（a-

1
2
）2+
3
4
≥
3
4
，∵f（x）在[0，+∞]上是减函数，

∴f（a2-a+1）≤f（

3
4
）．又f（x）是偶函数，∴f（-
3
4
）=f（
3
4
）．

∴f（a2-a+1）≤f（-

3
4
）

故答案为：f（a2-a+1）≤f（-

3
4
）

改错题

     假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。错误涉及一个单词的增加、删除或修改。

     增加：在缺词处加一个漏字符号(^)，并在其下面写出该加的词。

     删除：把多余的词用斜线(＼)划掉。

     修改：在错误的词下划一横线，并在该词下面写出修改后的词。

     注意： 1.每处错误及其修改均仅限一词。 

                 2.只允许修改10处，多者（从第11处起）不计分。

     Almost all parents in China hope their son or daughter will have happy future. They are very strict with

their children, and so do teachers in schools! Many children are giving so much home- work that they have

hardly any spare time to have sports. The children are forbidden to do anything but study. There is no wonder

there're so many children are tired of their lessons. Some even attack or kill their parents or teachers! I strong

believe many people had already read this kind of news in newspapers or magazines. Shouldn't we draw a

lesson from the accident? Now our government is carrying on a plan to solve the education problems.

_________________________________________________________________________________________
查看答案
单项选择题 案例分析题

某校地理兴趣小组利用假期对当地的一个山谷进行野外考察，并绘制了如下地形剖面图。实线为等压面，虚线为等温面，箭头为大气流动方向。据此回答小题。

若图中信息只有一处正确，则地理兴趣小组的观测时间可能是（）。

A.8：00—9：00

B.12：00—13：00

C.15：00—16：00

D.23：00—24：00
查看答案