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The quadratic equation x^2+b x+4=0 will have real roots if

Options

  1. Ab -4 only
  2. Bb 4 only
  3. C-4 b 4
  4. Db -4, b 4

Correct answer

D. b -4, b 4

Step-by-step solution

Quadratic equation have real roots if discriminant D 0b^2-4.1 .4 0 or, b^2 16 or, b 4 and b -4

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