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For the function f(x) = 4 log e (x – 1) – 2x 2 + 4x + 5, x > 1, which one of the following is NOT correct ?

1. f is increasing in (1, 2) and decreasing in (2, ∞ )
2. f(x) = –1 has exactly two solutions
3. f ′ (e) – f ′
4. < 0 (4) f(x) = 0 has a root in the interval (e, e + 1)

Correct answer: f ′ (e) – f ′

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