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4024/22 May/Jun 2025, Question 17: Inverse Functions

Cambridge O Level Mathematics 4024 · Paper 22 (Calculator) · Calculator · 3 marks

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The question, in short

For f(x) = (10 − x)/3 find f(−8), and for g(x) = 4x + 3 find the inverse function g⁻¹(x).

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Part (a) · 1 mark

Substitute x = −8 into f(x) = (10 − x)/3 and work out the value.

  1. 1f(−8) = (10 − (−8))/3 = 18/3 = 6

Answer6

Part (b) · 2 marks

Find the inverse of g(x) = 4x + 3, giving g⁻¹(x) in terms of x.

  1. 1y = 4x + 3; swap: x = 4y + 3
  2. 24y = x − 3
  3. 3g⁻¹(x) = (x − 3)/4

Answer(x −3)/4

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Also searched as: 4024/22/M/J/25 · 4024_s25_qp_22 · 4024 s25 22 · question 17.
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