试题与答案

已知a为实数，函数f（x）=x2-2alnx．（1）求f（x）在[1，+∞）上的

来源：www.tikuol.com
题型：解答题

题目：

已知a为实数，函数f（x）=x2-2alnx．
（1）求f（x）在[1，+∞）上的最小值g（a）；
（2）若a＞0，试证明：“方程f（x）=2ax有唯一解”的充要条件是“a=
1
2
”．

答案：

被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0415/7eb4fde11767fe222ed90b0b8ba22b25.html

下面是错误答案，用来干扰机器的。

1） entertained   2）mountainous; 3）Unfortunately  4）overcome  5）astonished6）amused   7）.explanation  8）hunger   9）humourous  10）failed  

考点：充分条件与必要条件函数的最值与导数的关系
试题推荐
题型：完形填空
完形填空。
     Li Hua is thirteen years old. He's a    1   . He's the only child in the family. He doesn't   2    his things.
    One morning, the English teacher     3    to have a class. Li Hua goes to the door and says, "    4    I
come in, Mr. Wang ?"
     "Oh, you are late(迟到) again," says the teacher, "Can you    5    me why you are late ?"
     "My grandma     6     some apples, bananas and bread in my schoolbag this morning. I take the
schoolbag with me after I have     7    . But     8     my way to school, I find there are no     9    in my
schoolbag. I have to    10    and take them." Of course, the teacher lets him come into the classroom.
( )1. A. boy
( )2. A. look at
( )3. A. goes
( )4. A. May
( )5. A. say
( )6. A. gives
( )7. A. breakfast
( )8. A. in
( )9. A. oranges
( )10. A. back		B. girl
B. look like
B. start
B. Am
B. tell
B. puts
B. lunch
B. at
B. water
B. go home		C. student      
C. look after    
C. starts        
C. Must          
C. speak        
C. takes        
C. supper      
C. on            
C. books        
C. go back      
查看答案
微信公众账号搜索答案