If p and q are the roots of the equation x^2 + px + q = 0

• Quadratic Equations

If p and q are the roots of the equation x² + px + q = 0, then

1. p = 1, q = -2
2. p = -2, q = 1
3. p = -2, q = 0
4. p = 0, q = 1

Answer

Given S = p + q = – p and product pq = q

This implies, q(p – 1) = 0 i.e. q = 0, p = 1

Now If q = 0 then p = 0, this implies p = q

If p = 1, then p + q = – p

q = – 2p

q = – 2(1)

q = – 2

The correct option is A.