ECZ 2017 · O-Level Paper 1 — Relations and Functions
The functions f and g are defined by f(x) = 2x + 1 and g(x) = 5x − 1. Find g-1(x).
- A. 5x + 1
- B. x − 15
- C. x + 15
- D. 15x − 1
Verified working — step 1
The inverse undoes g - a rearrangement, never a reciprocal. Set y = g(x), make x the subject, then swap the letters.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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