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Let f(x) = x3 − 62 + 9𝑥 + 18, then f(x) is strictly decreasing in ______

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Question

Let f(x) = x3 − 6x2 + 9𝑥 + 18, then f(x) is strictly decreasing in ______

Options

  • (−∞, 1)

  • (3, ∞)

  • (−∞, 1) ∪ (3, ∞)

  • (1, 3)

MCQ
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Solution

(1, 3)

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Chapter 2.2: Applications of Derivatives - MCQ

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