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问题 解答题
已知f(x)=(x
1
k
+x)n，且正整数n满足Cn3=Cn5，A={0，1，2，…n}
（1）求n；
（2）若i、j∈A，是否存在j，当i≥j时，Cni≤Cnj恒成立．若存在，求出最小的j；若不存在，试说明理由．
（3）k∈A，若f（x）的展开式有且只有三个有理项，求k．
答案

（1）根据题意中Cn3=Cn5，结合Cnm=Cnn-m，

则n=8

（2）由（1）的结论，n=8，

当n=8时，C8m（m=0、1、2…、8）中，C84最大，

即i≥j≥4时，满足Cni≤Cnj恒成立，

则最小的j=4；

（3）f(x)=(x

1
k
+x)8展开式通项为Tr+1=
Cr8
(x
1
k
)8-r•xr=
Cr8
x
8-r
k
+r

依题意，只须8-r是k的整数倍的r有且只有三个，

分别令k=1，2，3…8，代入通项中，

检验得k=3或4；

故k=3或4．

单项选择题 A1型题

磺脲类药降糖的主要作用是（）

A.加速无氧糖酵解

B.促进外周组织摄取葡萄糖

C.刺激胰岛β细胞释放胰岛素

D.抑制肠道对葡萄糖的吸收

E.增强靶组织对胰岛素敏素感性
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问答题

Part 1


·Read the following passages, eight sentences have been removed from the article.
·Choose.from the sentences A-H the one which fits each gap.
·For each gap (1-8) mark one letter (A-H) on the Answer Sheet.
·Do not mark any letter twice.
Today’s career assumptions are you can get a lot of development, challenge and job satisfaction and not necessarily be in a management role.
A new malady is running rampantly in corporate America: management phobia. (1)
" I hated all the meetings," says a 10-year award-winning manager, "and I found the more you did for people who worked for you, the more they expected." (2)
With technology changing in a wink, you can never slack off these days if you’re on the technical side. (3)
In addition, the Dilbert factor is at work. With Scott Adams’s popular cartoon character— as well as many television sitcoms — routinely portraying managers as morons or enemies, they just don’t get much respect anymore.
Supervising others was always a tough task, but in the past that stress was offset by hopes for career mobility and financial rewards. (4)
But in today’s global, more competitive arena, a manager sits on an insecure perch. (5) There are far fewer rungs on the corporate ladder for managers to climb. In addition, managerial jobs demand more hours and headaches than ever before but offer slim, if any, financial paybacks and perks.
Furthermore, managers now must supervise many people who are spread over different locations, even over different continents. (6)
In an age of entrepreneurship, when the most praised people in business are those launching something new, management seems like an invisible, thankless role. (7)
Management layoffs have done much to erode interest in managerial jobs, of course. (8)
A. Many people don’t want to be a manager — and many people who are managers are, frankly, itching to jump off the management track — or have already.
B. It’s a rare person who can manage to keep up on the technical side and handle a management job, too.
C. Restructuring have eliminated layer after layer of management as companies came to view their organizations as collections of competencies rather than hierarchies.
D. They must manage across functions with, say, design, finance, marketing and technical people reporting to them.
E. I was a counselor, motivator, financial adviser and psychologist.
F. Employers are looking for people who can do things, not for people who make other people do things.
G. American Management Association surveys say three middle managers are laid off for every one being hired.
H. Along with a sizable pay raise, people chosen as managers would begin a nearly automatic climb up the career ladder to lucrative executive perks: stock options, company cars, club memberships, plus the key to the executive washroom.
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