Which of the following is the fully simplified form of (15x3y^2)/(20x5y^4)?
A) 3/(4x2y^2)
B) 3x2y^2/4
C) 3/(4xy2)
D) 15/(20x2y^2)
(Total for Question 1 is 1 mark)
2
Simplify each fraction fully.
(a)Simplify fully (24x6y^3)/(16x2y^5)(2)
(b)Simplify fully (18a5b^2)/(27a2b^7)(2)
(Total for Question 2 is 4 marks)
3
Simplify each fraction fully by factorising first.
(a)Simplify fully (5x+15)/(x2+3x)(3)
(b)Simplify fully (8x-24)/(x2-3x)(3)
(Total for Question 3 is 6 marks)
4
Simplify fully (x2+6x+8)/(x2+2x-8)
(Total for Question 4 is 3 marks)
5
Simplify each fraction fully, using difference of two squares where needed.
(a)Simplify fully (x2-49)/(x2+4x-21)(3)
(b)Simplify fully (9x2-4)/(3x2+4x-4)(3)
(Total for Question 5 is 6 marks)
6
Simplify each product fully.
(a)Simplify fully (4x/3y) x (9y3/8x2)(3)
(b)Simplify fully (10a2/7b3) x (14b5/25a4)(3)
(Total for Question 6 is 6 marks)
7
Simplify each quotient fully.
(a)Simplify fully (6x3/5y2) / (9x/10y)(3)
(b)Simplify fully (8a4/3b) / (12a/9b4)(3)
(Total for Question 7 is 6 marks)
8
Simplify fully (x+4)/(x2-9) x (x-3)/(3x+12)
(Total for Question 8 is 4 marks)
9
Simplify fully (x2-4)/(x+5) / (x-2)/(4x+20)
(Total for Question 9 is 4 marks)
10
Priya is asked to simplify (x2-16)/(x-4) and writes the answer as x-16.
(a)Explain the mistake Priya has made.(1)
(b)Work out the correct fully simplified answer.(2)
(Total for Question 10 is 3 marks)
11
Show that (2x2+9x+4)/(x2-16) simplifies to (2x+1)/(x-4)
(Total for Question 11 is 3 marks)
12
Simplify fully (10-2x)/(x2-25)
(Total for Question 12 is 3 marks)
13
Simplify fully (2x2-5x-3)/(x2-9)
(Total for Question 13 is 3 marks)
14
Simplify fully (8+2x-x2)/(x2-x-12)
(Total for Question 14 is 4 marks)
15
Simplify fully (x2+7x+12)/(x2-16) x (x2-4x)/(x2+x-6)
(Total for Question 15 is 4 marks)
16
Simplify fully (2x2-3x-2)/(x2-4) / (2x+1)/(x-2)
(Total for Question 16 is 4 marks)
17
Simplify fully (x4-81)/(x2-9)
(Total for Question 17 is 4 marks)
18
A rectangular tile has area (x2-4)/(x+3) cm2 and length (x-2)/(x2-9) cm. Find an expression for the width of the tile in its simplest form.
(Total for Question 18 is 5 marks)
19
(x2-2x-15)/(x2-25) x (x2+5x)/(x2+8x+15)
(a)Simplify the expression above fully.(5)
(b)Hence find the value of the expression when x=10, giving your answer as a fraction in its simplest form.(2)
(Total for Question 19 is 7 marks)
20
Simplify fully (x2-6x+9)/(x2-9) / (3-x)/(x+3)
(Total for Question 20 is 5 marks)
Mark scheme · A1 Algebraic Fractions: Simplifying, Multiplying and Dividing
Question 1
B1 correct option identified (A) oe
Answer: A) 3/(4x2y^2)
Question 2
(a) M1 numeric coefficient simplified to 3/2 oe
(a) A1 3x4/(2y2) cao
(a) Answer: 3x4/(2y2)
(b) M1 numeric coefficient simplified to 2/3 oe
(b) A1 2a3/(3b5) cao
(b) Answer: 2a3/(3b5)
Question 3
(a) M1 numerator factorised as 5(x+3)
(a) M1 denominator factorised as x(x+3)
(a) A1 5/x cao
(a) Answer: 5/x
(b) M1 numerator factorised as 8(x-3)
(b) M1 denominator factorised as x(x-3)
(b) A1 8/x cao
(b) Answer: 8/x
Question 4
M1 numerator factorised as (x+2)(x+4)
M1 denominator factorised as (x+4)(x-2)
A1 (x+2)/(x-2) cao
Answer: (x+2)/(x-2)
Question 5
(a) M1 numerator factorised as (x-7)(x+7)
(a) M1 denominator factorised as (x+7)(x-3)
(a) A1 (x-7)/(x-3) cao
(a) Answer: (x-7)/(x-3)
(b) M1 numerator factorised as (3x-2)(3x+2)
(b) M1 denominator factorised as (3x-2)(x+2)
(b) A1 (3x+2)/(x+2) cao
(b) Answer: (3x+2)/(x+2)
Question 6
(a) M1 multiplies numerators and denominators: 36xy3/(24x2y) oe
(a) M1 numeric coefficient simplified to 3/2 oe
(a) A1 3y2/(2x) cao
(a) Answer: 3y2/(2x)
(b) M1 multiplies numerators and denominators: 140a2b^5/(175a4b^3) oe
(b) M1 numeric coefficient simplified to 4/5 oe
(b) A1 4b2/(5a2) cao
(b) Answer: 4b2/(5a2)
Question 7
(a) M1 inverts second fraction and multiplies: (6x3/5y2)(10y/9x) oe
(a) M1 numeric coefficient simplified to 4/3 oe
(a) A1 4x2/(3y) cao
(a) Answer: 4x2/(3y)
(b) M1 inverts second fraction and multiplies: (8a4/3b)(9b4/12a) oe
(b) M1 numeric coefficient simplified to 2 oe
(b) A1 2a3b^3 cao
(b) Answer: 2a3b^3
Question 8
M1 x2-9 factorised as (x-3)(x+3)
M1 3x+12 factorised as 3(x+4)
M1 cancels (x+4) and (x-3) correctly
A1 1/(3x+9) oe cao
Answer: 1/(3x+9)
Question 9
M1 inverts second fraction and factorises x2-4 as (x-2)(x+2)
M1 4x+20 factorised as 4(x+5)
M1 cancels (x-2) and (x+5) correctly
A1 4x+8 oe cao
Answer: 4x+8
Question 10
(a) B1 identifies that x2-16 must first be factorised as (x-4)(x+4) as a difference of two squares before any cancelling, rather than cancelling the 16 and the 4 as separate terms oe
(a) Answer: Priya cancelled individual terms (16 and 4) instead of factorising the numerator first.
(b) M1 factorises x2-16 as (x-4)(x+4)
(b) A1 x+4 cao
(b) Answer: x+4
Question 11
M1 numerator factorised as (2x+1)(x+4)
M1 denominator factorised as (x-4)(x+4)
A1 cancels (x+4) correctly to reach (2x+1)/(x-4) cso
Answer: (2x+1)/(x-4)
Question 12
M1 numerator factorised as -2(x-5)
M1 denominator factorised as (x-5)(x+5)
A1 -2/(x+5) oe cao
Answer: -2/(x+5)
Question 13
M1 numerator factorised as (2x+1)(x-3)
M1 denominator factorised as (x-3)(x+3)
A1 (2x+1)/(x+3) cao
Answer: (2x+1)/(x+3)
Question 14
M1 rewrites numerator as -(x2-2x-8)
M1 factorises x2-2x-8 as (x-4)(x+2) and x2-x-12 as (x-4)(x+3)
M1 cancels (x-4) correctly, retaining the negative sign
A1 -(x+2)/(x+3) oe cao
Answer: -(x+2)/(x+3)
Question 15
M1 factorises x2+7x+12 as (x+3)(x+4) and x2-16 as (x-4)(x+4)
M1 factorises x2-4x as x(x-4) and x2+x-6 as (x+3)(x-2)
M1 cancels (x+3), (x+4) and (x-4) correctly
A1 x/(x-2) oe cao
Answer: x/(x-2)
Question 16
M1 inverts second fraction and factorises 2x2-3x-2 as (2x+1)(x-2)
M1 factorises x2-4 as (x-2)(x+2)
M1 cancels (2x+1) and one factor of (x-2) correctly
A1 (x-2)/(x+2) oe cao
Answer: (x-2)/(x+2)
Question 17
M1 recognises x4-81 as a difference of two squares (x2)2 - 92
M1 factorises to (x2-9)(x2+9)
M1 cancels (x2-9) with the denominator
A1 x2+9 cao
Answer: x2+9
Question 18
M1 sets up width = area / length
M1 factorises x2-4 as (x-2)(x+2) and x2-9 as (x-3)(x+3)
M1 inverts the length fraction and multiplies correctly
M1 cancels (x-2) and (x+3) correctly
A1 (x+2)(x-3) oe, or x2-x-6, cao
Answer: (x+2)(x-3), which expands to x2-x-6
Question 19
(a) M1 factorises x2-2x-15 as (x-5)(x+3) and x2-25 as (x-5)(x+5)
(a) M1 factorises x2+5x as x(x+5) and x2+8x+15 as (x+3)(x+5)
(a) M1 cancels (x-5) and (x+3) correctly
(a) M1 cancels one remaining factor of (x+5) correctly
(a) A1 x/(x+5) oe cao
(a) Answer: x/(x+5)
(b) M1 substitutes x=10 into x/(x+5) ft from part (a)
(b) A1 2/3 oe cao
(b) Answer: 2/3
Question 20
M1 factorises x2-6x+9 as (x-3)2
M1 factorises x2-9 as (x-3)(x+3)
M1 recognises 3-x = -(x-3)
M1 inverts the second fraction and multiplies, cancelling (x-3)2 and (x+3) correctly