人教课标版B5 Unit 1 Great Scientists Workbook-Reading task +14张
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| 名称 | 人教课标版B5 Unit 1 Great Scientists Workbook-Reading task +14张 |  | |
| 格式 | zip | ||
| 文件大小 | 1.0MB | ||
| 资源类型 | 教案 | ||
| 版本资源 | 人教版（新课程标准） | ||
| 科目 | 英语 | ||
| 更新时间 | 2015-08-29 18:00:30 | ||
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课件14张PPT。人教课标
高二 必修 5 Unit 1Reading taskon Page 44Unit 1 Great scientistsWhat’s Euler’s puzzle?
Koningsberg is an island and there is a river breaking it into two parts. “Seven Bridges of Konigsberg” and the famous “Euler path”.People wondered if they could walk around the city by crossing the seven bridges without going over any of them twice or going back on himself, but Euler found he couldn’t cross all the seven ones. This is Euler’s puzzle. The first stage in his research is to find the problem that he could cross six of the bridges without going over any of them twice or going back on himself, but he couldn’t cross all seven. How did Euler prepare for his research?The second stage is to think of a
method: He drew a map and used
dots and lines to simplify his analysis.
Trying and observing over and over
again, he found a general rule. It is topology. Euler’s theory is called “The Euler path”, which is expressed like this: If a figure has more than two odd points, you cannot go over it without lifting your pencil from the page or going over a line twice. What are the theories?So the general rule that Euler found is the even points and the odd points.Look at the following pictures:Conclusion
Euler’s theory (一笔画)
可以一笔画只有两种情况：
1. 没有奇数顶点。
2. 只有两个奇数顶点。 Thank you!
高二 必修 5 Unit 1Reading taskon Page 44Unit 1 Great scientistsWhat’s Euler’s puzzle?
Koningsberg is an island and there is a river breaking it into two parts. “Seven Bridges of Konigsberg” and the famous “Euler path”.People wondered if they could walk around the city by crossing the seven bridges without going over any of them twice or going back on himself, but Euler found he couldn’t cross all the seven ones. This is Euler’s puzzle. The first stage in his research is to find the problem that he could cross six of the bridges without going over any of them twice or going back on himself, but he couldn’t cross all seven. How did Euler prepare for his research?The second stage is to think of a
method: He drew a map and used
dots and lines to simplify his analysis.
Trying and observing over and over
again, he found a general rule. It is topology. Euler’s theory is called “The Euler path”, which is expressed like this: If a figure has more than two odd points, you cannot go over it without lifting your pencil from the page or going over a line twice. What are the theories?So the general rule that Euler found is the even points and the odd points.Look at the following pictures:Conclusion
Euler’s theory (一笔画)
可以一笔画只有两种情况：
1. 没有奇数顶点。
2. 只有两个奇数顶点。 Thank you!