[PP Sub Inspector 17 Aug 2021] 

9. Which of the following options gives the correct formula for finding the roots of a quadratic equation of the form ?

\(ax^2 + bx + c = 0\)

1. \(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\)

2. \(x = {-b \pm \sqrt{b^2-ac} \over 2a}\)

3. \(x = {-b \pm \sqrt{b^2-6ac} \over 2a}\)

4. \(x = {+b \pm \sqrt{b^2-4ac} \over 2a}\)

Correct Answer :

\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\)