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 fg(−3).

  • A. 29
  • B. −29
  • C. −31
  • D. 31

Verified working — step 1

Build the composite rule fg(x) first, then substitute x = -3 into it.

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Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.

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