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Find the values of x for which the function f(x) = 2x3 – 6x2 + 6x + 24 is strictly increasing

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प्रश्न

Find the values of x for which the function f(x) = 2x3 – 6x2 + 6x + 24 is strictly increasing

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उत्तर

f(x) = 2x3 – 6x2 + 6x + 24

∴ f′(x) = 6x2 – 12x + 6

= 6(x2 – 2x + 1)

= 6(x – 1)2

f(x) is strictly increasing, if f′(x) > 0

∴ 6(x – 1)2 > 0

∴ (x – 1)2 > 0 for all x ∈ R, x ≠ 1

Thus, f(x) is strictly increasing for x ∈ R – {1}.

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अध्याय 2.2: Applications of Derivatives - Short Answers I

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