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If both p and q belong to the set (1,2,3,4) , then how many equations of the form p x^2+q x+1=0 will have real roots?

Options

  1. A12
  2. B10
  3. C7
  4. D6

Correct answer

C. 7

Step-by-step solution

p, q 1,2,3,4 For real roots q^2 4 p If q=1, p= If q=2, p=1 If q=3, p=1,2 If q=4, p=1,2,3,4 7 such pairs exist.

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