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问题 单项选择题

已知x1，x2是方程
x2+(k+1)x+(k2+2k-2)＝0
的两个实根，求

的最大值．

答案

参考答案：

解析：解：由已知条件，有x1+x2＝-(k+1)，x1x2＝k2+2k-2．所以，＝(x1+x2)2-2x1x2＝(k+1)2 -2(k2+2k-2)
＝-k2-2k+5
＝-(k+1)2+6≤6
即当k＝-1时，

有最大值6．

单项选择题

With the widespread use of the personal computer, many authorities in the field of (56) have pointed out the need for computer literacy.

Unfortunately, there is no (57) agreement as to what the term "computer literacy" means. Some feel that computer literacy means knowing how to make the computer "compute"; that is knowing how to program computers in one or more programming languages.

Others feel that knowing how to program is merely a small segment of computer literacy. These people (58) the major emphasis in schools should be on teaching how to effectively use the many software packages that are available.

Still others suggest that computer literacy education is not required. They suggest that computers are being so rapidly integrated into our society that using a computer will be as (59) as using a telephone or a video tape recorder, and that special education will not be necessary. (60) of one’s definition of computer literacy, it is recognized by most that learning to use a computer is indeed an important skill in modern society.

56（）

A.culture 

B.science 

C.education 

D.industry
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多项选择题

下列属于我国“四项基本原则”的是（）。

A.坚持中 * * 党的领导

B.坚持人民代表大会制

C.坚持马克思列宁主义、毛 * * 思想

D.坚持社会主义道路
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