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AP EAMCET2009MathematicsProbability

The probability of choosing randomly a number c from the set 1,2,3, , 9 such that the quadratic equation x^2+4 x+c=0 has real roots is

Options

  1. A1 9
  2. B2 9
  3. C3 9
  4. D4 9

Correct answer

D. 4 9

Step-by-step solution

Given, x^2+4 x+c=0 For real roots, aligned D & =b^2-4 a c 0 & =16-4 c 0 aligned c=1,2,3,4 will satisfy the above inequality. Required probability = 4 9

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