# Quod Erat Demonstrandum

## 2008/04/28

### 上課雜談

Filed under: Junior Form Mathematics — johnmayhk @ 4:04 下午

（一）乖

（二）危與機

1. Once upon a time, the Pythagoras’ theorem was called 『勾股弦定理』in Chinese，what is the meaning of『弦』？ Why we may simplify the name of the theorem as 『勾股定理』？

2. Use your own language and/or mathematical symbols to explain the following statement 『勾股各自乘，並而開方除之，即弦』.

3. It is claimed in the article that『近年來許多學者主張廢除將定理冠以畢達哥拉斯之名』, do you agree with the scholars? Why?

4. Suppose a, b and c are positive integers（正整數）satisfying a^2 + b^2 = c^2, then (a , b , c) is called Pythagorean triplet（畢達哥拉斯三元數組）. We know that (3 , 4, 5) , (5 , 12 , 13) are Pythagorean triplets. Given that (2007 , b , c) is a Pythagorean triplet, find possible values of b and c.

（三）轉貼

他的『新、舊牢騷集』有不少文章，或多或少可以反映老師的心聲，值得讀讀。

## 4 則迴響 »

1. Hi…
you don’t get used to shouting, and that’s why I knew that you’ve not corrected their behavior… Well, I just wanna tell you that Miss Wong ask, I don’t mean to say that you must come^_^, if that I’m misleading…
Anyway, I dunno the reason every time I had a hair cut, it was always a new look or something else… Is it the question of my “dead head" or is it the problem of me…? Every time they ask me how to do do that job, I would just say = MAKE IT SHORTER… And if you’ve not noticed that, you’re so blind…

迴響 由 Edmund — 2008/04/28 @ 6:18 下午 | 回應

2. 恰巧今天代課的時候，也向一班中三學生，說關於worldline，light cone 的東西，再說了一些愛因斯坦怎樣想出狹義相對論
竟然有學生在午飯時，繼續問我更深入的東西。
(不過我想聽得懂的也只有幾個)

迴響 由 Daniel — 2008/04/29 @ 7:50 下午 | 回應

3. To Daniel

你說的話題非常有趣，可惜我是物理外行，深入的也不懂了。有學生以好奇求知的態度發問，叫當老師的甚為欣喜。

今天我又要代堂了。

To Edmund

Yep, I’m so blind. Next time, you may try to tell the barbar exactly what you want.

迴響 由 johnmayhk — 2008/04/30 @ 9:19 上午 | 回應

4. " THINKING MAKES YOU DIFFERENT !"

迴響 由 MARK K. C. MA — 2009/04/01 @ 11:24 上午 | 回應