ECZ 2021 · O-Level Paper 1 — Relations and Functions
The functions f and g are defined by f(x) = x + 92 and g(x) = x − 2. Find f-1(x).
- A. x − 92
- B. 2x + 9
- C. 2x − 9
- D. x2 − 9
Verified working — step 1
The inverse undoes f. The recipe: set y = f(x), make x the subject, then swap the letters back.The full step-by-step working and final answer, plus the video lesson for this topic, are included with Premium — checked against ECZ marking standards.
Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.
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