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MHT CET202619 April 2026Evening ShiftMathematicsFunctionsActual

If g(x) = 1 - x and f(g(x)) = 5 + 4 x + x , then the value of f(6) is...

Options

  1. A5
  2. B10
  3. C15
  4. D20

Correct answer

B. 10

Step-by-step solution

Given g(x) = 1 - x and f(g(x)) = 5 + 4 x + x . Let y = g(x) = 1 - x . Then x = 1 - y and x = (1 - y)^2 . Substituting these into the equation for f(g(x)) : f(y) = 5 + 4(1 - y) + (1 - y)^2 To find f(6) , substitute y = 6 into the equation: f(6) = 5 + 4(1 - 6) + (1 - 6)^2 f(6) = 5 + 4(-5) + (-5)^2 f(6) = 5 - 20 + 25 = 10 Answer: 10

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