摘要：习题14．1．1-1.2.3.4题．
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观察下列解题过程
计算：1+5+52+53+…+524+525
解：设S=1+5+52+53+…+524+525①
则5S=5+52+53+…+524+525+526②
②-①的：4S=526-1，∴S=
．
你能用你学到的方法计算下面的题吗？
1+3+32+33+…+39+310 查看习题详情和答案>>
计算：1+5+52+53+…+524+525
解：设S=1+5+52+53+…+524+525①
则5S=5+52+53+…+524+525+526②
②-①的：4S=526-1，∴S=
| 526-1 | 4 |
你能用你学到的方法计算下面的题吗？
1+3+32+33+…+39+310 查看习题详情和答案>>
观察下列各式：
=1-
，
=
-
，
=
-
，…
（1）请依据以上的式子填写下列各题：
①
=
-
-
；
②
=
-
-
．（n为正整数）
（2）根据上面各式所归纳的规律计算下题：
+
+
+…+
+
；
（3）拓展延伸：
如果a=1，b=3，计算下题：
+
+
+…+
．
查看习题详情和答案>>
| 1 |
| 1×2 |
| 1 |
| 2 |
| 1 |
| 2×3 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 3×4 |
| 1 |
| 3 |
| 1 |
| 4 |
（1）请依据以上的式子填写下列各题：
①
| 1 |
| 8×9 |
| 1 |
| 8 |
| 1 |
| 9 |
| 1 |
| 8 |
| 1 |
| 9 |
②
| 1 |
| n(n+1) |
| 1 |
| n |
| 1 |
| n+1 |
| 1 |
| n |
| 1 |
| n+1 |
（2）根据上面各式所归纳的规律计算下题：
| 1 |
| 1×2 |
| 1 |
| 2×3 |
| 1 |
| 3×4 |
| 1 |
| 2008×2009 |
| 1 |
| 2009×2010 |
（3）拓展延伸：
如果a=1，b=3，计算下题：
| 1 |
| ab |
| 1 |
| (a+1)(b+1) |
| 1 |
| (a+2)(b+2) |
| 1 |
| (a+98)(b+98) |
小明和小红回答6道题的分数如下：
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完形填空 （20分）
The famous British inventor George Stephenson was born in 1781 and died in 1848. one of his _21_ important inventions was the train. He _22_his first train when he was forty-four years old. When he was experimenting with the _23_ engine on the train, he met with _24_ from the government, newspapers and the gentlemen in the country. They said that the noise and the smoke would _25_ cows, horses and sheep, that the _26_ would hurtle(炸飞) or that the hot coals from it would _27_their houses. At that time, _28_ people believed what they said.
George Stephenson _29_ the people that the train could go on small _30_, could pull carriages _31_goods and passengers and there was _32_ to them. It was a very _33_ matter for him to _34_ them believe. However, after _35_, he was able to do it; and the first train that _36_ by Stephenson himself _37_ what he had said.
The first day _38_ the people along the way _39_ the noises of the train _40_ and saw it running quickly to them, they ran back home as quickly as they could and closed their doors tightly, for they thought it a genius. They did not dare to come out until it had passed.
【小题2】made B. bought C. introduced D. did
【小题10】 A.reads B. rivers C. steam D rails
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The famous British inventor George Stephenson was born in 1781 and died in 1848. one of his _21_ important inventions was the train. He _22_his first train when he was forty-four years old. When he was experimenting with the _23_ engine on the train, he met with _24_ from the government, newspapers and the gentlemen in the country. They said that the noise and the smoke would _25_ cows, horses and sheep, that the _26_ would hurtle(炸飞) or that the hot coals from it would _27_their houses. At that time, _28_ people believed what they said.
George Stephenson _29_ the people that the train could go on small _30_, could pull carriages _31_goods and passengers and there was _32_ to them. It was a very _33_ matter for him to _34_ them believe. However, after _35_, he was able to do it; and the first train that _36_ by Stephenson himself _37_ what he had said.
The first day _38_ the people along the way _39_ the noises of the train _40_ and saw it running quickly to them, they ran back home as quickly as they could and closed their doors tightly, for they thought it a genius. They did not dare to come out until it had passed.
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