# Quod Erat Demonstrandum

## 2010/07/27

### 物奧和其他的一些報導

Filed under: Report — johnmayhk @ 3:48 下午
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（文匯報　2010-07-27）

[FW] 物理奧賽獲獎 中四生創紀錄 本港參賽7年來最年幼得獎者 5港生獲1金1銀3銅

(記者　周婷)

## 2010/07/26

### MVT 某推廣

Filed under: HKALE,Pure Mathematics — johnmayhk @ 11:54 上午
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$F(x) = -3x + \frac{\pi}{2}\cos(\frac{\pi}{2}x) + \frac{e^x}{e - 1} + \frac{1}{(x + 2)\ln 2}$ 在區間 (0,1) 存在零點 ………. (*)

$F(0) , F(1)$ 皆大於零，故不宜用介值定理（Intermediate Value Theorem）。

## 2010/07/22

### 暑期無聊閱讀

Filed under: Additional / Applied Mathematics,HKALE,HKCEE — johnmayhk @ 9:02 上午
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If you worked for a mining company the following might be a typical problem:

There are two intersecting mine shafts that meet at an angle of 123$^o$, as shown in the figure above. The straight shaft has a width of 7 feet, while the entrance shaft is 9 feet wide. What is the longest ladder that can be negotiate the turn? You can neglect the thickness of the ladder members, and assume it is not tipped as it is maneuvered around the corner. Your solution should provide for the general case in which the angle, A, is a variable, as well as the widths of the shafts. (more…)

## 2010/07/16

### 奧數新聞

Filed under: Report — johnmayhk @ 9:31 上午
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[FW] 港中學生擬題 首獲奧數「徵用」

## 2010/07/05

### [FW] Chimps make monkeys out of humans

Filed under: Uncategorized — johnmayhk @ 9:37 下午

Old news but still very interesting…