2019年2月20日星期三

2019 DSE Mock Examination Package

2019 DSE Mathematics / M1 / M2 Mock Examination Package 終於推出喇!

內容包括:

  • 完整試卷(英文 / 中文 二選其一)
  • 完整答案
  • 完整考試表現報告
  • 考試表現示例
  • 改卷服務(可選)


2019年2月19日星期二

一條有趣的幾何問題

最近有學生問左我以下既問題,幾值得係道討論下:



In the above figure, AD = BC and BD = CD. Also, ∠ABD = 70° and ∠BCD = 10°. Find ∠BAD.

呢題看似唔難,如果有讀 M2 同學都可以用 trigonometry 既方法做到,方法可以係最底搵到。

當然讀 Core 既同學仔其實都會計到呢題啦!等大家諗下先啦~~~

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我地今次想講既方法就係係 D 個道畫一條 line segment DP 令到 DP = BP、∠ADP = 10° 同埋 ∠BDP = 60°。

跟住,你就發現由於 S.A.S. 既關係, △ADP 同埋 △BCD 係 congruent 架,所以我地就有 AP = BD 同埋 ∠DAP = 10° (而由 ∠ sum of △ 亦可得出 ∠APD = 160°)喇!

然後,你亦會發現 △BDP 係 equilateral,因此 BP = BD = AP (因此由 base ∠s, isos. △ 可知 PAB = PBA)及 ∠BPD = 60°。

另外,由 ∠s at a pt. 可知 APD 係 140°,由 ∠ sum of △ 就可以計到 BAP = 20°。

所以 BAD 就係 30° 喇!!!


好多時候,deductive geometry 都會比到我地一個更 elementary (唔需要用到諸如 M2 呢類唔係個個同學都識既)同更加靚既方法去做一條數,而呢d 加線既方法都係要靠見多d 唔同既題目去慢慢累積架!

所以,同學仔都要做多d 數同埋試下諗下唔同既方法去做一條數啊!

當然,去到考試既話,MC 就諗到就可以用番 trigonometry 方法之後計數機計番出 answer 啊!



FYI 使用 M2 Trigonometry 的方法:

2020 DSE Extended Star Capturing Course

2020 DSE Extended Star Capturing Course 是一個為期兩年的課程,把 DSE 所有有關知識、題型、伏位均傳授給每位同學,而教學次序更以矢志奪星的你應有的溫習數學科的課題次序排列,教完整個課程後更有 26 份 Jacky Sir 自製數學 Mock 卷操練,以令各位同學可以以最佳方法於 DSE 奪星!

每期內容



Lesson 1 – 4
Laws of integral indices
Introduction to polynomials
Simultaneous linear equations
Identities and factorization
Formulae
Ratios and rates
Percentages
Simple linear inequalities
Approximation and error
The scientific notation
Different numeral systems
The number system
Lesson 5 – 8
Quadratic equations in one unknown
Compound linear inequalities
Quadratic inequalities
Complex numbers
Lesson 9 – 12
Functions and graphs
Lesson 13 – 16
Polynomials
Rational functions
More about equations
Lesson 17 – 20
Variations
Exponential functions and logarithmic functions
Lesson 21 – 24
Arithmetic sequences and geometric sequences
Linear programming
Gift for finishing Lessons 1 – 24: Prelude to 5** 2020 Volume 1
Lesson 25 – 28
Terminologies in geometry
Symmetry and transformation
Simple deductive geometry
The four important centres of triangles
Lesson 29 – 32
Simple trigonometry
Trigonometric functions
Mensuration
Lesson 33 – 36
Applications of trigonometry
Lesson 37 – 40
Basic properties of circles
Simple coordinate geometry
Equations of straight lines
Lesson 41 – 44
Equations of circles
Loci
The polar coordinate system
Lesson 45 – 48
Permutations and combinations
Probabilities I
Gift for finishing Lessons 1 – 48: Prelude to 5** 2020 Volume 2
Lesson 49 – 52
Probabilities II
Statistics
Gift for finishing Lessons 29 – 52: A Mock Examination Set
Lesson 53 – 56
Revision on algebra
Gift for finishing Lessons 1 – 36: Prelude to 5** 2020 Volume 3
Lesson 57 – 60
Revision on geometry
Lesson 61 – 64
8 Mock Examinations (on 8 separate days)
Gift for finishing Lessons 1 – 64: Prelude to 5** 2020 Volume 4
Lesson 65 – 68
8 Mock Examinations (on 8 separate days)
Lesson 69 – 72
8 Mock Examinations (on 8 separate days)
Gift for finishing Lessons 1 – 72: Prelude to 5** 2020 Volume 5

由於課程安排問題,2020 DSE Extended Star Capturing Course 將於 2019 年 3 月 31 日後停止收生,所以如果要加入奪星行列,就要盡快報名喇!

2020 DSE 課程詳情及報名表格
2021 DSE 課程詳情及報名表格