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JEE Advanced2014MathematicsApplication of DerivativesActual

Let a ∈ R and let f : R → R be given by f x = x 5 - 5 x + a , then

Options

  1. Af x has three real roots if a > 4
  2. Bf x has only one real roots if a > 4
  3. Cf x has three real roots if a < - 4
  4. Df x has three real roots if - 4 < a < 4

Correct answer

B. f x has only one real roots if a > 4

Step-by-step solution

Let y = x 5 - 5 x

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