passwella.
Menu

JAMB Mathematics 2002 Question 21

Question 21

Algebraic Expressions

The inverse of the function f(x) = 3x + 4 is

  1. A.(1/3)(x − 4)
  2. B.(1/5)(x − 5)
  3. C.(1/4)(x + 3)
  4. D.(1/3)(x + 4)
Show the answer and explanation

Answer: A ((1/3)(x − 4))

Explanation

Put y = 3x + 4 and solve for x: x = (y − 4)/3. So f−1(x) = (1/3)(x − 4).