IGCSE · Additional Mathematics 0606 · Algebra

Functions: IGCSE Additional Mathematics questions with answers

Free Functions questions for IGCSE Additional Mathematics (0606), part of Algebra. Each question has the answer and the marking points an examiner would look for.

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Functions practice questions

Question 1Structured · 6 marksA* challenge

f(x) = |4x − 8|

(a)

Sketch the graph of y = f(x), stating the coordinates of the points where it meets the axes.

[3]
(b)

Solve f(x) = 4.

[3]
Show answers and mark scheme
PartAnswer and marking pointsMarks
(a)(2, 0) and (0, 8)
V shape with vertex on x-axis B1
(2, 0) B1
(0, 8) B1
3
(b)x = 1, x = 3
4x − 8 = ±4 M1
x = 3 A1
x = 1 A1
3
Question 2Structured · 5 marks

f(x) = (x + 3)2 + 4 for x ≥ −3

(a)

State the range of f.

[1]
(b)

Find f−1(x) and state its domain.

[3]
(c)

Describe how the graphs of y = f(x) and y = f−1(x) are related.

[1]
Show answers and mark scheme
PartAnswer and marking pointsMarks
(a)f(x) ≥ 4
f(x) ≥ 4 B1
1
(b)−3 + √(x − 4), x ≥ 4
swap x and y and rearrange M1
f−1(x) = √(x − 4) − 3 A1
domain x ≥ 4 B1
3
(c)reflection in y = x
reflection in the line y = x B1
1
Question 3Structured · 6 marks

f(x) = 4x + 6 for x ∈ ℝ g(x) = 4x − 1 for x > 1

(a)

Find f−1(x).

[2]
(b)

Find the range of g.

[1]
(c)

Solve fg(x) = 22.

[3]
Show answers and mark scheme
PartAnswer and marking pointsMarks
(a)x − 64
correct method M1
x − 64 A1
2
(b)g(x) > 0
g > 0 B1
1
(c)x = 2
f(g(x)) = 16x − 1 + 6 M1
16x − 1 = 16 M1
x = 2 A1
3
Question 4Structured · 3 marks
(a)

State what is meant by the term inverse function.

[1]
(b)

State what is meant by the term one-one function.

[2]
Show answers and mark scheme
PartAnswer and marking pointsMarks
(a)A function that reverses the effect of a one-one function
A function that reverses the effect of a one-one function B1
1
(b)A function in which each value in the range comes from exactly one value in the domain
A function in which each value in the range comes from exactly one value in the domain B2
2
Question 5Structured · 6 marksA* challenge

f(x) = |3x − 6|

(a)

Sketch the graph of y = f(x), stating the coordinates of the points where it meets the axes.

[3]
(b)

Solve f(x) = 3.

[3]
Show answers and mark scheme
PartAnswer and marking pointsMarks
(a)(2, 0) and (0, 6)
V shape with vertex on x-axis B1
(2, 0) B1
(0, 6) B1
3
(b)x = 1, x = 3
3x − 6 = ±3 M1
x = 3 A1
x = 1 A1
3
Question 6Structured · 5 marks

f(x) = (x − 1)2 + 3 for x ≥ 1

(a)

State the range of f.

[1]
(b)

Find f−1(x) and state its domain.

[3]
(c)

Describe how the graphs of y = f(x) and y = f−1(x) are related.

[1]
Show answers and mark scheme
PartAnswer and marking pointsMarks
(a)f(x) ≥ 3
f(x) ≥ 3 B1
1
(b)1 + √(x − 3), x ≥ 3
swap x and y and rearrange M1
f−1(x) = √(x − 3) + 1 A1
domain x ≥ 3 B1
3
(c)reflection in y = x
reflection in the line y = x B1
1

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Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in