Answer:
The minimum value = -38
Step-by-step explanation:
∵ f(x) = x² - 12x - 2
∵ -12x ÷ 2 = -6x ⇒ -6 × x
∴ (x - 6)² = x² - 12x + 36
∴ Add and subtract 36 in f(x)
∴ f(x) = (x² - 12x + 36) - 36 - 2
∴ f(x) = (x - 6)² - 38 ⇒ completing square
∴ The vertex of the parabola is (6 , -38)
∵ Its minimum point because the coefficient of x² is positive
∴ The minimum value = -38
1. Replace f(x) with y: y = 3x - 15
2. Interchange x and y: x = 3y - 15
3. Solve this for y: 3y = x + 15, and y = (x + 15)/3
4. Replace y with
-1 -1
f (x): f (x) = (x + 15) / 3 (answer)
Answer: c
Step-by-step explanation: