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If the function f given by f(x) = x 3 – 3(a – 2)x 2 + 3ax + 7, for some a ∈ R is increasing in (0, 1] and decreasing in [1, 5), then a root of the equation, 0 ) 1 x ( 14 ) x ( f 2 = − − (x ≠ 1) is :

1. –7
2. 5
3. 7
4. 6

Correct answer: 7

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