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The function f x = 2 x 3 - 3 a + b x 2 + 6 a b x has a local maximum at x = a, if

Options

  1. Aa > b
  2. Ba < b
  3. Ca > 0
  4. Da < 0

Correct answer

B. a < b

Step-by-step solution

f &#x2032; x = 6 x 2 &#x2212; a + b x + a b = 6 x - a x - b i.e. f x has local maximum at x = a if a < b

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