(Ⅰ)设α1,α2,β1,β2均是三维列向量,且α1,α2线性无关,β1,β2线性无

题型:问答题

问题:

(Ⅰ)设α1,α2,β1,β2均是三维列向量,且α1,α2线性无关,β1,β2线性无关,证明存在非零向量ξ,使得ξ既可由α1,α2线性表出,又可由β1,β2线性
(Ⅱ) 当


由α1,α2线性表出,又可由β1,β2线性表出的向量.

考点:普通考研考研数学(一)考研数学一
题型:问答题

已知:a、b互为相反数,c、d互为倒数,m的绝对值是5,求代数式1998(a+b)-3cd+2m的值.

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以下哪项是中医临床的基本诊察手段()

A.叩

B.触

C.望

D.听

E.视

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1957年10月,( )把世界第一颗人造卫星送上太空,标志着航天技术的诞生,揭开了太空技术的序幕。

A.美国
B.前苏联
C.中国
D.欧共体

题型:问答题

Since we are social beings, the quality of our lives depends in large measure on our interpersonal relationships. One strength of the human condition is our tendency to give and receive support from one another under stressful circumstances. Social support consists of the exchange of resources among people based on their interpersonal ties.

Those of us with p support systems appear better able to cope with major life changes and daily hassles (困难). People with p social ties live longer and have better health than those without such ties. Studies over a range of illnesses, from depression to heart disease, reveal that the presence of social support helps people fend off (挡开) illness, and the absence of such support makes poor health more likely.

Social support cushions stress in a number of ways. First, friends, relatives, and co-workers may let us know that they value us. Our self-respect is strengthened when we feel accepted by others despite our faults and difficulties. Second, other people often provide us with informational support. They help us to define and understand our problems and find solutions to them. Third, we typically find social companionship supportive. Engaging in leisure-time activities with others helps us to meet our social needs while at the same time distracting (转移……注意力) us from our worries and troubles. Finally, other people may give us instrumental support—financial aid, material resources, and needed services—that reduces stress by helping us resolve and cope with our problems.

Interpersonal relationships are important because ().

A. they are indispensable to people’s social well-being

B. they waken people’s desire to exchange resources

C. they help people to cope with life in the information era

D. they can cure a range of illnesses such as heart disease, etc.

题型:问答题

在可比实例的成交日期至估价时点期间,无论房地产价格为上涨、下跌或平稳发展,都必须进行交易日期调整。 ( )

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