10 questions · Form 2 Mathematics Bab 2: Factorisation and Algebraic Fractions
Simplify the expression: (2x3) + (x4).
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. Simplify the expression: (2x3) + (x4).
Answer: B
Find the LCM of 3 and 4, which is 12: (2x × 412) + (x × 312) = 8x12 + 3x12 = 11x12.
2. Simplify: 1 - x - 23.
Answer: A
Combine under common denominator 3: 3 - (x - 2)3 = 3 - x + 23 = 5 - x3.
3. Factorise 5p + 5q - ap - aq completely.
Answer: C
Group terms: 5(p + q) - a(p + q) = (5 - a)(p + q).
4. What is the expanded form of (3a - 2b)²?
Answer: C
Using identity (x - y)² = x² - 2xy + y²: (3a)² - 2(3a)(2b) + (2b)² = 9a² - 12ab + 4b².
5. Factorise completely: 3x² - 12.
Answer: B
First factor out 3: 3(x² - 4). Then apply difference of squares: 3(x + 2)(x - 2).
6. Expand: 2(x - 3) - 3(2 - x).
Answer: A
Expand each term: 2x - 6 - 6 + 3x = (2x + 3x) + (-6 - 6) = 5x - 12.
7. Factorise x² - 49.
Answer: B
Using difference of two squares a² - b² = (a + b)(a - b): x² - 7² = (x + 7)(x - 7).
8. Factorise the quadratic expression: x² - 7x + 12.
Answer: C
Find two numbers that multiply to +12 and add up to -7. The numbers are -3 and -4. So, (x - 3)(x - 4).
9. Express x² - 9x + 3 in its simplest form.
Answer: B
Factorise the numerator: (x + 3)x - 3x + 3 = x - 3.
10. If the area of a rectangle is (x² + 6x + 8) cm² and its length is (x + 4) cm, find its width.
Answer: A
Width = Area ÷ Length = x² + 6x + 8x + 4 = (x + 4)(x + 2)x + 4 = x + 2 cm.