Q.

If the quadratic equation ax² + bx + c = 0, a ≠ 0 has two real and equal roots, then ‘c’ is equal to

1 −b/2a  
2 b/2a  
3 −b²/4a  
4 b²/4a  

Ans.

(4)

Given quadratic equation ax² + bx + c = 0, a ≠ 0.
For real and equal roots, discriminant = 0.

⇒ b² − 4ac = 0 ⇒ b² = 4ac ⇒ c = b²/4a