定义域为（0，+∞）的可导函数f（x）满足xf′（x）＞f（x）且f（2）=0，则
|
因为xf′（x）＞f（x），所以[
]′=[xf′（x）-f（x）]f(x) x
＞0，1 x2
即F（x）=
在定义域内递增函数，又因F（2）=f(x) x
=0，f(2) 2
则不等式
＜0的解集就是不等式F（x）＜F（2）的解集，解得{x|0＜x＜2}．f(x) x
故选A．
Questions 29-40
· Read the information about the communication of information in business.
· Choose the correct word to fill each gap from A, B or C.
· For each question (29-40) mark one letter A, B or C on your Answer Sheet.
| A number of business people still believe that information is power and constantly question how (29) people need to know. As a result, they tell employees (30) as much as they think is essential (31) them to do particular jobs. Furthermore, (32) business people have been taught (33) to communicate effectively and (34) they communicate very badly at all levels. Recent research shows that (35) most serious problems experienced by modern business are communication (36) Research has also shown that there is a clear link (37) good communication in a business and the motivation of the employees. Newsletters and notices are not (38) It is the attitude and behavior of business managers which (39) all the difference. Unfortunately, at present, a lot of employees do not believe all the information they receive from their managers (40) they feel that the managers themselves are out of touch with their staff. |
A．
| A. too much |
B．
| B. enough |
C．
| C. too little |