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问题 解答题
设函数f(x)=
4x-1
4x+1
（1）解不等式f(x)＜
1
3
；（2）求函数f（x）的值域．
答案

（1）将f（x）的解析式代入不等式得：

4x-1
4x+1
＜
1
3
，

整理得：3•4x-3＜4x+1，即4x=22x＜2=21，

∴2x＜1，

解得：x＜

1
2
，

则不等式的解集为{x|x＜

1
2
}；

（2）法一：f（x）=

4x-1
4x+1
=1+
-2
4x+1
，

∵4x＞0，∴4x+1＞1，

∴-2＜

-2
4x+1
＜0，

∴-1＜1+

-2
4x+1
＜1，

则f（x）的值域为（-1，1）；

法二：∵y=f（x）=

4x-1
4x+1
，

∴4x=

y+1
1-y
＞0，即
y+1
y-1
＜0，

可化为：

y+1＞0
y-1＜0
或
y+1＜0
y-1＞0
，

解得：-1＜y＜1，

则f（x）的值域为（-1，1）．

单项选择题

"Intelligence" at best is an assumptive construct--the meaning of the word has never been clear. It is generally agreed that a person of high intelligence is one who can grasp ideas (1) , make distinctions, reason logically, and (2) verbal and mathematical symbols in solving problems. An intelligence test is a rough measure of a child’s (3) for learning, particularly for learning the kinds of things required in school. It does not (4) character, social adjustment, physical endurance, manual skills, or artistic abilities. It is not (5) to--it was not designed for such (6) . To criticize it for such failure is roughly (7) criticizing a thermometer for not measuring wind velocity.

The other thing we have to notice is that the assessment of the intelligence of the (8) is essentially a comparative affair.

(9) the assessment of intelligence is a comparative matter we must be sure that the (10) with which we are comparing our subjects provides a "valid" and " (11) " comparison. It is here (12) some of the difficulties which interest us begin. Any test (13) involves at least three factors: the (14) to do one’s best, the knowledge required for understanding what you have to do, and the (15) ability to do it. In school populations in our culture these assumptions can be made fair and reasonable, and the value of intelligence testing has been (16) thoroughly. Its value (17) , of course, in its providing a satisfactory basis for prediction. No one is (18) interested in the marks a little child gets on his test; what we are interested in is whether we can (19) from his mark on the test that the child will do better or worse than other children of his age in (20) which we think require "general intelligence".

Read the following text. Choose the best word(s) for each numbered blank and mark [A] , [B] , [C] or [D] on ANSWER SHEET I.20（）

A．respects

B．honors

C．angles

D．distinctions
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单项选择题

依据《企业所得税法》规定，下列企业所得中不属于“可以免征、减征企业所得税”的是：

A．从事农、林、牧、渔业项目的所得
B．符合条件的居民企业之间的股息、红利等权益性投资收益
C．从事符合条件的环境保护、节能节水项目的所得
D．从事国家重点扶持的公共基础设施项目投资经营的所得
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