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If f x is a continuous function such that its value ∀ x ∈ R is a rational number and f 1 + f 2 = 6 , then the value of f 3 is equal to

Options

  1. A3
  2. B9
  3. C2
  4. D4

Correct answer

A. 3

Step-by-step solution

Since f x is continuous and attains only rational values, then by intermediate value theorem, f x is a constant function. i.e. f 1 = f 2 = 3

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