標題: [M2] 2018 core math M1 M2 分析 [小小意見, 歡迎討論] [打印本頁] 作者: kchowhm 時間: 2018-5-2 08:20 AM 標題: 2018 core math M1 M2 分析 [小小意見, 歡迎討論]
小小意見, 歡迎討論
DSE Core math 2018 分析
Paper 1
Section A1
Q1 Change subject, easy
Q2 indice, easy
Q3 round up/down/off, easy
Q4 simple probability, easy
Q5 Factorization, easy, 留意 part b 9r^2 – s^2 要再factorize, 技巧翻炒2015
Q6 inequality, easy
Q7 Percentage (cost, profit/loss, discount, selling price) 少少難, 因為冇分part a/b, 但ok的, 可能會令能力稍遜的學生失分
Q8 Circles, concept is easy, 題型新穎, 因為沒有數字, 答案 in terms of theta, 但ok的
Q9 Simultaneous equations cross over speed, 出得好, 留意分鐘和小時的單位轉換, 可能會令能力稍遜的學生失分
Section A2
Q10 Statistics (measures of dispersion)
Part a easy, part b 要試試下先會理解題目, 可能會令能力稍遜的學生失分
Q11 Statistics (mean, mode, median)
出得好, part b 係容易失分位 (但可以用不等式做的), 其餘四分穩袋
Q12 典型polynomial
Part b 的 irrational root有點tricky, 應該有部分學生在這part判斷錯誤
Q13 Plane geometry
a) Similar triangle, past paper常客, let 某隻角係y 就可以用AA係證
b) All easy
Q14 Mensuration
Part b use similar ratio, all easy
Section B
Q15 P&C
新題型, 但唔難
Q16 ASGS
Part a 輕鬆
Part b 少少難, 翻炒2012 and 2013 last question, 但可以接受
Q17 3D trigo
a) Sine formula, 輕鬆
b) (i) cosine formula, 輕鬆
(ii) 攬炒
Q18 Variation + completing square + 四心
Part a, b i easy
Part b ii 考 transformation of graph
Part c modified from 2015 Q18, 應該都ok的
Q19 **題, 一題定勝負
a) 大家都知道用delta搵tangent, 鬥爆數, 用x做subject應該做唔到, 用y做subject就會砌到, this is the biggest hurdle of this year’s paper 1
b) (i) 做得part a 的話, 呢part冇難度, 但值得留意的係, 做唔到part a 的, 因為佢而家話左D的座標比你聽, 你係可以起死回生的………….
(ii) inscribed circle, in-centre, angle bisectors, tangent properties, not difficult actually, but 6 marks ar…….
Paper 2
Section A
Q1 indice, easy
Q2 change subject, easy
Q3 factorization, 要調位先, easy
Q4 rational function, easy
Q5 quadratic function and graph, easy
Q6 difficult straight line MC, 早左出現, 建議飛左先
Q7 function, cut and paste, easy
Q8 polynomial, easy
Q9 compound interest, easy
Q10 ratio, easy
Q11 variation, easy
Q12 simple sequence, 少少難…
Q13 compound inequality, easy
Q14 error, upper limit 減 lower limit……..
Q15 volume of prism, easy
Q16 ratio geometry, this year is easy comparatively…
Q17 difficult plane geometry 1. wow! 要用similar triangles幫手計
Q18 plane geometry 2. Wow! 要用congruent triangles幫手計
Q19 difficult plane geometry 3. wow! Wow!
Q20 difficult plane geometry 4. wow! 要用similar triangles幫手計 or trigo
Q21 wow, trigo
Q22 circle, easy comparatively..
Q23 easy, rotational symmetry
Q24 polar coordinate, need to draw graph
Q25 locus, easy
Q26 straight line, need to draw graph
Q27 equation of circle, easy
Q28 probability, you may draw table, ok easy
Q29 find mean, easy
Q30 IQR.. 少少難
Section B
Q31 transformation of graph, ok
Q32 log graph, 少少難
Q33 log straight line graph, ok
Q34 linear programming, fxxk, 要畫圖, 仲要唔易畫, crazy
Q35 ASGS, easy
Q36 sum of roots/ product of roots, ok
Q37 imaginary number, ok
Q38 trigo equation, easy
Q39 circle, angle in alt. segment, ok
Q40 4 centres, need to draw graph, 少少難
Q41 又係呢d 3D trigo, 少少難
Q42 P&C, easy
Q43 probability + GS, modified from 2014 paper 1 Q19
Q44, standard score, easy
Q45 variance, 出得有新意, ok ar
Q3 Trigo, 有d tricky, 首先大家要將個condition: cot A = 3 cot B 化成 cos A sin B = 3 sin A cos B, 之後就 prove 到 sin (A+B) = 2 sin (B-A). 這個a part 出得比往年有d唔同, 但可以接受及出得不錯. 能力稍遜的學生未必做到
Part b 都 tricky, 首先 put A = x + 4pi/9, B =x + 5pi/18 這個是明顯的, 之後要留意到右邊會變左 -2sin(3pi/18), 即係 -1, 咁就有得做. 跟住要知道 2x + 13pi/18 的range 係 13pi/18 同 31pi/18 之間, 即係話 1.5pi 可以係答案, 最後就會計到 7pi/18
Q4 M1常用的公式出左喺M2: differentiate 5^u = 5^u ln 5
不懂呢條公式的M2人做by parts時會比較吃力, 這題看得出這個organization有點9
但如果你識呢條公式, part a 輕鬆
至於part b, find area, of course use part a la. 留意要將 u put做 2x, 之後用返 part a 就ok
呢條應該又differentiate 一d能力稍遜的學生
Q5 a) integration by substitution, easy
b) find tangent, easy too
Q6 (翻炒2016 Q5)
a) MI, easy
b) 小心做, 明白 summation sign運作的輕鬆做到
Q7 matrix, easy
Q8 a) 搵f’(x), 因為冇話 in terms of A, 所以學生要記得搵返A
b) 幾有新意的出法, 但又考到學生, 學生要完全明白三款asymptotes的運作, 仲要表達清楚, 呢一part可能會令部分學生減1-2分
c) 少少難d, 但可以接受, ok 的, 要check sign, 否則減一分
Q9 Application of differentiation (rate of change)
modified from 2016 Q3
畫圖準確係key
a) Ok的, 畫圖準確係key
b) 少少難d, 但也ok, 畫圖準確係key, 要check sign to show why it is maximum, 記得subs.返e^2 搵返個area
c) 難呀, 要砌式 (Pyth thm), 又難d, 不過出得好好
Q10 Integration (M2 Section B 常客)
a) i) 少少難, 錯方向就死死地, 要將sin x dx 變做 -d cos x, 試啱方向的話就輕鬆
ii) just use a i, easy
b) i) past paper出過若干次, 大家穩袋
ii) use b i and a ii, 輕鬆
c) 少少難
Q11 System of linear equations
Part a 的9分完全係2016 Q11 part a 的9 分, 送禮呀, 但大家用Cramer’s rule (克萊瑪) 做的時候要小心, 又係鬥爆數
Q2 a) confidence interval, easy, 留意 a i 係 (0.0915+0.3085)/2, 唔係減
b) 要理解題目可能有少少難
Q3 a) normal distribution, easy
b) Geometric distribution, also easy
Q4 Expected value/Variance, easy
Q5 d, in, limit, easy, 留意 part a要做 first derivative test
Q6 Expand e^x & binimial expansion, ok easy
Q7 easy differentiation involving square root sign, need to reject h=4.0625
Q8 d and in switch, part c 計 area, easy too, 要加absolute sign
Section B
Q9 a) normal distribution, easy
b) binomial distribution, easy
c) i) ok difficult
ii) and iii) if c i ok, here no problem
Q10 Poisson distribution
a) easy
b) Very good question, use expected value to judge, not difficult though
c) i) easy too
ii) a little bit complicated calculation, but ok bor
Q11 a) trapezoidal rule, standard question
b) i) integration by substitution, easy
ii) need to be careful
Q12 a) ln graph slope y-intercept, easy
b)i) a little bit clumsy, but ok
ii) Subs. t=0
iii) iv) 完全翻炒2015 Q12... 留意part iv係問dN/dt的變化, need to use d2N/dt2 to judge..
