Mathematics for IGCSE & O level - Algebraic Manipulation (Section 4 - No. 29)
For expressions in the form ax² + bx + c, when is the middle term negative?
When both factors of c are negative
When the constant term c is negative
When one factor of c is positive and one is negative and the larger magnitude factor is negative
Never
Giải thích
The middle term's sign depends on the signs of the factors of c, and on which is larger.