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问题 单项选择题

设α1，α2，α3是四元非齐次线性方程组AX=b的三个解，秩(A)=3，k任意实数，则AX=b的通解X=（）。

A．α1+k(α1-α2-α3)

B．α1+k(α1+α2+α3)

C．α1+k(2α1-α2-α3)

D．α1+k(3α1-2α2-2α3)

答案

参考答案：C

解析：

由于α1-α2-α3不是AX=0的解，故选项A不正确；由于α1+α2+α3不是AX=0的解，故选项B不正确；

由于3α1-2α2-2α3=2(α1-α2)+(α1-α3)-α3不是AX=0的解，故选项D不正确；

由于2α1-α2-α3=(α1-α2)+(α1-α3)是AX=0的解，秩(A)=3的基础解系由一个解向量组成，故k(α1-α2-α3)是AX=0的通解，故正确答案为C。

综合

读“我国四大地理区域示意图”，回答下列问题。(14分)

（1）“北风卷地百草折，胡天八月即飞雪”是描述我国四大区域中的______地区(填字母)，该地区主要属__________区(季风区、非季风区)。

（2）有两种农作物柑橘和青稞，其中柑橘最适宜种植在______(填字母)地区，青稞最适宜种植在_______(填字母)地区。

（3）D地区太阳能资源非常丰富，简析其原因。_________________________________________________。

（4）简要说明C地区的民居屋顶相对平缓的原因。___________________________________________________。
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填空题


It is clear that we are rapidly becoming a global culture. New forms of information technology, intercontinental travel, and the complex nature of economics are all elements in such a change. Japan, an ancient (1) culture, now dominates the West economically while its own traditional (2) is rapidly becoming (3) in the process.
It does not take a great deal of analysis to see the vast interchanges of cultural influences in the world today. The thirst for (4) fashions, popular music, and the other elements of consumer culture (5) great inroads in non-Western lands while the West seeks out everything from the religious traditions of the Ease (6) the art and music these countries produce. In the field of (7) , to cite one conspicuous example, contemporary readers seek books (8) those of the West. Latin American authors, as well as those from Africa, Asia, and India, now find appreciative audiences.
A (9) culture does not mean a unitary or "one world" culture. It does mean that people are increasingly aware of the diversity of culture. World events enter our living rooms so that things that may once have been (10) of as distant (11) now greet us immediately and in color. We may watch those events on a television made in Japan while wearing clothes sewn in Thailand and shoes made in Hungary while snacking (12) food grown in Mexico. Such an economic interdependence reflects the reality of a global banking system, the globalization of the economy, and the increasing (13) of information and information technologies.
(14) has this shrinking of distances (and attitudes) become more clear than in the academic debates over what constitutes a liberal (15) education today. Is it possible (or desirable) to have the Western core of humanities (16) the center-piece of a curriculum The place of non-Western and non-traditional cultures as part of the general (17) of a student is hotly argued in educational circles. The very fact of that discussion (18) to the emergence of a global consciousness with a continued shrinking of parochial attitudes. The (19) that such globalization is hotly debated only emphasizes the profound nature of the (20) taking place in our culture.
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