ECZ 2024 · O-Level Paper 1 — Relations and Functions
Given that f(x) = 3x + 5 and g(x) = x + 43, find gf(4).
- A. 17
- B. 4
- C. 7
- D. 15
Verified working — step 1
Build the composite rule first, then substitute. In gf(x) the function written nearest to x acts first: work out f(x), then feed the whole result into g.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.
Have a different question?
Search it — if it is from a past paper or a school mock, chances are we have it worked out, or one that uses the same method.
Search any past-paper question