# Definition:Discriminant of Polynomial/Quadratic Equation

## Definition

Consider the quadratic equation:

$a x^2 + b x + c = 0$

The expression $b^2 - 4 a c$ is called the discriminant of the equation.

## Also see

Note that this is a special case of the general discriminant, although it is important to note that the general formula is given for monic polynomials.