What is the inverse function of f(x) = 3x - 6?
Answer and explanation
Correct answer: D. (x + 6)/3
- Step 1: Let y = 3x - 6; solve for x: x = (y + 6)/3. Step 2. Swap the variables: f^-1(x) = (x + 6)/3. Answer: (x + 6)/3. Why not the others: (x - 6)/3: The 6 must be added when undoing the subtraction. 3x + 6: That does not undo both steps. 1/(3x - 6): That is the reciprocal, not the inverse.
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