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Let g(x) = 3f ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ 3 x + f(3 – x) and f''(x) > 0 for all x ∈ (0, 3). If g is decreasing in (0, α ) and increasing in ( α , 3), then 8 α is:

1. 24
2. 18
3. 20
4. 0

Correct answer: 18

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