题目内容

数列{an}的前n项和Sn=n2+2n+5，则an+1+an+2+an+3=()

A. n2+6n
B. 6n+15
C. n2+6n+15
D. 6n
E. 以上答案均不正确

查看答案

搜索结果不匹配？点我反馈

更多问题

Which of the following is the best title for the passage？

A. Human Behavior.
B. Creatures of Society.
C. The Science of Custom.
D. The Functions of Culture.

查看答案

Which of the following does the author most probably agree with？

A. The goal of the anthropology is to understand the way in which people express themselves.
B. The anthropologist tries to understand why cultures are carried on without any change.
C. The anthropologist's professional interest is as wide as the variety of customs.
D. All of the above.

查看答案

According to this passage, housewives ______.

A. are not satisfied with the present standard of living
B. think that domestic servants are very helpful
C. will prefer to live a life with more free time
D. hope that the husband will be better paid by the employers

查看答案

听力原文：M: I'm terribly sorry. I'm late.
W: I've only been waiting for over an hour, that's all.
M: Yes, I know, I... I tried to get here in time, but just after I left home, the car broke down.
W: The car broke down？
M: Yes, and.., well.., luckily.., there was a garage near me, and.., and it took them a while to repair it.
W: Why didn't you at least phone？
M: I would have! But I didn't know the number of the restaurant.
W: You could have looked it up in the telephone book!
M: Yes, but... You'll never believe this... I couldn't remember the name of the restaurant. I knew where it was, but forgot the name.
W: I see, well, it was lucky you find a garage to repair your car.
Q8. Why did the man apologize？
9.Where did they plan to meet？
10.How long has the woman been waiting for？
(8)

A. His car broke down.
B. He forgot the telephone number.
C. He was late for the appointment.
D. He couldn't remember the name of the restaurant.

查看答案

数列{an}的前n项和Sn=n2+2n+5，则an+1+an+2+an+3=()

A. n2+6n B. 6n+15 C. n2+6n+15 D. 6n E. 以上答案均不正确

Which of the following is the best title for the passage？

Which of the following does the author most probably agree with？

According to this passage, housewives ______.

A. n2+6n
B. 6n+15
C. n2+6n+15
D. 6n
E. 以上答案均不正确