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问题 填空题
已知单位向量
a
，
b
的夹角为120°，当|2
a
+x
b
|（x∈R）取得最小值时x=______．
答案

因为单位向量

a
，
b
的夹角为120°

所以|2

a
+x
b
|2=4
a
2+4x
a
•
b
+x2
b
2

=x2-2x+4=（x-1）2+3

∴当x=1时|2

a
+x
b
|2取最小值，此时|2
a
+x
b
|（x∈R）取得最小值，

故答案为：1

阅读理解
请阅读下列应用文及相关信息，并按照要求匹配信息。请在答题卡上将对应题号的相应选项字母涂黑。
首先，请阅读下面六封申请奖学金的书信：
A
Dear Sir or Madam,
I should like to apply for one of the scholarship that your department may be offering to students from other countries. I have graduated from Southeast Normal University since 2009. I major in French Language Education.
Thank you for your consideration. I look forward to your reply.
Very sincerely yours,
(Signature)
B
Dear Sir,
I am a postgraduate student in Beijing Science and Engineering University. I major in microelectronics engineering, and do some research work during my study years. I hope to have a future study and continue to do my research work if I succeed in obtaining the engineering scholarship. Would you please send me the necessary application forms and any further details about the scholarship.
Respectfully yours,
(Signature)
C
Dear Sir,
I am writing to you in the hope of obtaining the scholarship in history to support my study and some research work.
I am a graduate student in the Department of History in the Northeast University for Nationalities. In addition to study and research work, I also write books. Recently I have finished a book on the history of Origin nationality in China. I would like to focus on that field for my advanced studies.
Thank you for your time and consideration. I look forward to your reply.
Respectfully yours,
(Signature)
D
Dear Sir or Madam,
I would be most grateful if you would send me details of graduate study facilities or scholarships in civil engineering which University of Lancaster may be offering to students from overseas. I majored in engineering and graduated from Fudan University in 2008. I have studied English for more than 7 years up to intermediate（中间的）level. If any scholarships are available, I would appreciate it if you would send me the necessary application forms.
Sincerely yours,
(Signature)
E
Dear Dr. Gomes,
I have read the announcement of the scholarship in chemistry that the University of Colorado is offering, and I would like to submit my application.
The enclosed application form for admission to the graduate school of your university will give my educational history. However, I would like to point out that I have just received an M.S.
Sincerely yours,
(Signature)
F
Dear Dr. Brown,
I shall be obliged if you sent me the necessary application forms of scholarships in philosophy which University of Omaha may be offering to students from other countries. I graduated from Zhongshan University in 2009, and majored in philosophy. Please give my application the first consideration. I look forward to your reply.
Very truly yours,
(Signature)
请阅读以下奖学金申请者的信息，然后匹配申请者和他或她的申请。
小题1:Sun Xiaohong: Sun has graduated from Fudan University and majored in civil engineering. Her English is up to intermediate level.
小题2:Wu Mingming: Wu is a postgraduate student in Beijing Science and Engineering University, and majors in microelectronics engineering.
小题3:Wang Xin: Wang has just received an M.S. He majored in chemistry when he was in the university.
小题4:Li Liang: Li graduated from Zhongshan University a few years ago. He is very interested in philosophy.
小题5:Liu Jun: Liu is studying in the Northeast University for Nationalities. He wants to focus on the history of Origin nationality for his advanced studies.
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单项选择题 A1型题

按儿童计划免疫要求，儿童在1岁半至2岁半内应完成下列几种生物制品的接种（）

A.卡介苗、百日咳菌苗、麻疹、脊髓灰质炎疫苗

B.麻疹、脊髓灰质炎疫苗、白喉、破伤风类毒素

C.百日咳菌苗、麻疹、脊髓灰质炎疫苗、白喉类毒素

D.脊髓灰质炎疫苗、白喉、破伤风类毒素、卡介苗

E.卡介苗、百日咳、白喉、破伤风疫苗、脊髓灰质炎和麻疹疫苗
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