# Quod Erat Demonstrandum

## 2010/05/04

### 數數唸

Filed under: Junior Form Mathematics,mathematics — johnmayhk @ 3:49 下午

Estimate 120010 + 113030.

(a) 120010 + 113030　$\approx$ 100000 + 100000 = 200000，還是
(b) 120010 + 113030　$\approx$ 120000 + 110000 = 230000，還是
(c) 120010 + 113030　$\approx$ 120000 + 113000 = 233000？

(d) 120010 + 113030 = 233040 就是錯。

＂Polynomials are expressions containing more than one term, with each term separated from the preceding one by a plus or minus sign.＂

monomial 是 polynomial 的一種。

square 是 rectangle 的一種。

M2 開始談極限、無限等問題。回想自己中四開始接觸這個題目，心中興奮莫名。奇怪，我班同學卻好像被催眠似的。再如此這般，危殆。

## 9 則迴響 »

1. 極限、無限好好玩…
不過A.maths冇得玩….

今年份卷出得好"pastpaper"
唔似09咁多新野
不過今年無啦啦要玩摺紙,囧

迴響 由 Carmen — 2010/05/04 @ 5:33 下午 | 回覆

• 囧x2…出埋 extra worksheet 玩摺紙，未派卷前真係估佢唔到。

極限、無限好好玩…最慘係，想玩的人冇得玩，唔想玩就被迫玩。

迴響 由 johnmayhk — 2010/05/04 @ 6:31 下午 | 回覆

• 要摺咩咁得意@@?

迴響 由 Justin — 2010/05/05 @ 10:44 上午

2. I have seen the CE Paper (A MATH) today at the centre, section A a bit difficult, section B a bit easier than 09’s paper… but i think the curve will be a bit low, in my centre, i heard many students saying they can;t handle short q, some fail to do 3D too, my student ask me whether 90-92/110 can get A today? anyone suggets the range of curves for 2010 A MATHS…so i can answer my students… THANKS!!!
For previous pure maths paper, also LQ A BIT CHALLENGING…

迴響 由 Sam — 2010/05/04 @ 8:00 下午 | 回覆

3. @ Justin

未派卷，林 sir 問：A. Math 係咪有兩本 question paper？我即答：否。但昨天無啦啦多o左疊＂extra worksheet＂，即時驚一驚。

其實它是關於一道 3D 題目，以前也試過，可以讓考生撕開「摺」。只是以前在題目本內，今次額外弄一張，或許怕 scan 麻煩吧。

現在中學數學時興（其實興了很久了）玩摺紙，NSS 考生也要留意。

今次摺的不過是三角形。雖然讓同學撕出來摺，但比方說：

把三角形 ABC 對摺，使 AB 與 AC 重疊，同學卻也看不出「摺痕」其實是角 BAC 的角平分線。

看來，部分同學的空間感薄弱。

這其實是一道不錯的 TSA（BCA）題目。

@ Sam

Perhaps the setters of this year were warned to have some adjustment: increase the difficulty in SECTION A and decrease the difficulty in SECTION B. I don’t know whether the scores are given based on norm reference (may be a mixture of norm and standard reference, wild guess), btw scoring 90-92/110 is likely to obtain A. Some students said Q.10 (sq) is difficult, but at a glance, it is quite typical and trivial…sad but true…

迴響 由 johnmayhk — 2010/05/05 @ 12:15 下午 | 回覆

4. Ys, normally it requires to find dy/dx only, but this time it’s more creative, however I have taught my students to handle this, so I think no problem… But Section B seems to be a bit short, isn’t it? I really hope NSS will have more lengthy problems, so can test the ability of students to make use of information and their logical thinking!!!

迴響 由 Sam — 2010/05/05 @ 12:56 下午 | 回覆

5. 咁就冇左個a喇…我辜負左john sir…

迴響 由 FTL — 2010/05/06 @ 1:29 上午 | 回覆

6. 對我嚟講
極限、無限已經好好多
真係有興趣架…
但係呢排實在太多野做
晚晚都夜瞓…冇精神真係計唔到數

不過近來好左D啦
Trigo 果陣…計嚟計去都計唔到
對maths冇晒興趣
所有要計數嘅堂(maths + phy)
唔知點解係連眼都撐唔大=O=

而家對極限、無限好有興趣
對果d數學史?神秘符號?等等都勁有興趣
所以忙完呢幾個日應該會好D嘅…=]

↑純粹個人意見

PS: 我覺得爛Gag 可能可以提神…==
Keep 住佢地唔瞓
John Sir 可以試一試，睇下效果點

迴響 由 yU — 2010/05/06 @ 8:03 下午 | 回覆

• @ yU

這也是一個原因。不止老師，濟記學生也很忙。你們放學後的活動勁多：學生會、社、學會、義工、各項比賽、SBA、補習、測驗、會議…彼此也在捱。因為這裡是學校，不是補習社，不是單看學業成績的地方。我知你們也是很努力的！加油！

危急存亡，爛Gag救國？

第一，我唔識攪爛Gag。第二，好似加士百話齋：一係唔攪，一攪就要攪最好O既 Gag，唔好攪爛Gag。

迴響 由 johnmayhk — 2010/05/07 @ 3:19 下午 | 回覆