Test Academy | If f (x) = x³ – 6x² + 9x + 3 be a decreasing function, then x lies in (-∞, -1) ∩ (3, ∞), (1, 3), (3, ∞), None of these

Question

If f (x) = x³ – 6x² + 9x + 3 be a decreasing function, then x lies in

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