【DSE 數學 Paper 2 MC 技巧：節省時間及提高命中率】DSE Maths Paper 2 MC Techniques: Save Time and Raise Your Score
SketchMath 數學團隊 SketchMath Maths Team ｜ 更新 Updated 2026-10-20
Paper 2 有 45 題選擇題，限時 1 小時 15 分鐘，平均每題約 1 分 40 秒。先做容易的，卡住的先標記，稍後再回頭，不要留白，並善用捷徑：代入數值、測試點、排除選項及用計數機驗算。Paper 2 has 45 multiple-choice questions in 1 hour 15 minutes, about 1 minute 40 seconds each. Do the easy questions first, mark the slow ones and come back, never leave a blank, and use shortcuts: substitute numbers, test a point, eliminate options and check with the calculator.
若 a : b = 2 : 3，則 (a + b) : b 等於 A 2 : 3、B 5 : 3、C 1 : 3、D 5 : 2。If a : b = 2 : 3, then (a + b) : b equals A 2 : 3, B 5 : 3, C 1 : 3, D 5 : 2.
取 a = 2、b = 3：(a + b) : b = 5 : 3Take a = 2, b = 3: (a + b) : b = 5 : 3
答案： Answer: B
例題 2 Example 2：測試點 Test a point
x² − 5x + 6 < 0 的解是 A x < 2 或 x > 3、B 2 < x < 3、C x < 3、D x > 2。The solution of x² − 5x + 6 < 0 is A x < 2 or x > 3, B 2 < x < 3, C x < 3, D x > 2.
根是 2 及 3。測試 x = 2.5：6.25 − 12.5 + 6 = −0.25 < 0，所以中間的區間成立The roots are 2 and 3. Test x = 2.5: 6.25 − 12.5 + 6 = −0.25 < 0, so the middle interval works
測試 x = 0：6 > 0，所以兩側不成立Test x = 0: 6 > 0, so the outside does not work
答案： Answer: B
例題 3 Example 3：用計數機驗算 Check with the calculator
當 x ≠ 3，哪一項等於 (x² − 9)/(x − 3)？A x − 3、B x + 3、C x² − 3、D 3 − x。Which is equal to (x² − 9)/(x − 3) for x ≠ 3? A x − 3, B x + 3, C x² − 3, D 3 − x.
把 x = 5 代入原式：16 / 2 = 8Put x = 5 in the original: 16 / 2 = 8
⚠️ 不要在一題花四分鐘 Do not spend four minutes on one question先標記並選一個最可能的答案，然後繼續。每題分數相同，一題難題花的時間可以做兩題易題。Mark it, guess the most likely option, and move on. Each question is worth the same, so a hard one costs the time of two easy ones.
⚠️ 一個測試值可能同時符合兩個選項 One test value can accidentally fit two options避免用 0 或 1 這類會令多個選項相等的值。若仍有兩個選項符合，再試第二個值。Avoid values like 0 or 1 that make several options equal. If two options still survive, try a second value.
應該，必須填上答案。HKDSE 選擇題答錯不會倒扣分；細節請以考評局最新規定為準。
Yes, always fill in an answer. Wrong answers are not penalised in the HKDSE multiple-choice papers; check the current rules on the HKEAA site to be sure.
按課題做限時練習，檢討每一題用了超過兩分鐘的題目，並記住哪種捷徑適合哪種題型。
Practise timed sets by topic, review every question you took more than two minutes on, and learn which shortcut fits which type.