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NDA2023MathematicsApplication of DerivativesActual

Given that 4 x^2+y^2=9 What is the maximum value of xy?

Options

  1. A9 4
  2. B3 2
  3. C4 9
  4. D2 3

Correct answer

A. 9 4

Step-by-step solution

Since, y= 9-4 x^2 let f(x)=x y=x 9-4 x^2 So, maximum value of f(x) is 9 4

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