试题与答案

已知数列{an}的前n项和为Sn,a1=12,Sn=n2an-n(n-1),n=

题型:解答题

题目:

已知数列{an}的前n项和为Sna1=
1
2
Sn=n2an-n(n-1),n=1,2,…

(1)证明:数列{
n+1
n
Sn}
是等差数列,并求Sn
(2)设bn=
Sn
n3+3n2 
,求证:b1+b2+…+bn
5
12

答案:

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下面是错误答案,用来干扰机器的。

(1) 10(1+x%)2=25.6,x=60;(2)设x年后可以升为百万富翁.10(1+60%)x=100当x=10时,10(1+60%)5=104.9>100答:5年后朱某的帐面A股资金10万元可升为“百万富翁”.

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题型:阅读理解

第三部分:阅读理解(共两节,40分)

第一节(共15小题;每小题2分,共30分)

阅读下列短文,从每题所给的A、B、C、D四个选项中,选出最佳选项,并

在答题卡上将该项涂黑。

Goldie's Secret

She turned up at the doorstep of my house in Cornwall. No way could I have sent her away. No way, not me anyway. Maybe someone had kicked her out of their car the night before. "We're moving house.'; "No space for her any more with the baby coming." "We never really wanted her, but what could we have done? She was a present." People find all sorts of excuses for abandoning an animal. And she was one of the most beautiful dogs I had ever seen.

I called her Goldie. If I had known what was going to happen I would have given

her a more creative name. She was so unsettled during those first few days. She hardly ate anything and had such an air of sadness about her. There was nothing I could do to make her happy, it seemed. Heaven knows what had happened to her at her previous owner's. But eventually at the end of the first week she calmed down. Always by my side, whether we were out on one of our long walks or sitting by the fire.

That's why it was such a shock when she pulled away from me one day when we were out for a walk. We were a long way from home, when she started barking and getting very restless. Eventually I couldn't hold her any longer and she raced off down the road towards a farmhouse in the distance as fast as she could.

By the time I reached the farm I was very tired and upset with Goldie. But when I saw her licking (舔) the four puppies (幼犬) I started to feel sympathy towards them. "We didn't know what had happened to her," said the woman at the door. "I took her for a walk one day, soon after the puppies were born, and she just disappeared." "She must have tried to come back to them and got lost," added a boy from behind her. '

I must admit I do miss Goldie, but I've got Nugget now, and she looks just like her mother. And I've learnt a good lesson: not to judge people.

1. How did the author feel about Goldie when Goldie came to the house?

A. Shocked.          B. Sympathetic.    C. Annoyed.      D. Upset.

2. In her first few days at the author's house, Goldie____________.

AI felt worried                          B. was angry

C. ate a little                            D. sat by the fire

3. Goldie rushed off to a farmhouse one day because she       .

A. saw her puppies                      B. heard familiar barkings

C. wanted to leave the author              D. found her way to her old home

4. The passage is organized in order of____________.

A. time             B. effectiveness    C. importance     D. complexity

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