Location of rootsMediumQuestion 220010
Question
For x² + bx + c = 0 to have both roots positive, necessary conditions are:
- Ab > 0, c > 0
- Bb < 0, c > 0Correct
- Cb < 0, c < 0
- Db > 0, c < 0
Correct answer
b < 0, c > 0
Explanation
Both roots positive → sum = −b > 0 → b < 0. Product = c > 0. Both conditions needed.