Question

If the roots of a quadratic equation $ax^2 + bx + c = 0$ are equal but opposite in sign, then : (A) $a = 0$ (C) $b 
e 0$ (B) $b = 0$ (D) $a < b$

Accepted Answer

B. Let the roots be $\alpha$ and $-\alpha$. For a quadratic equation $ax^2 + bx + c = 0$, the sum of roots is given by $\alpha + (-\alpha) = -b/a$. Since $\alpha + (-\alpha) = 0$, we have $0 = -b/a$. This implies $b = 0$. Also, for roots to exist, $a 
e 0$.

Quadratic Equation Roots

Explanation

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