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A quadratic equation is a second-order polynomial equation in a single variable x
with a != 0
The roots x can be found using the quadratic formula
There are three cases:
then there are two distinct roots, both of which are real numbers
then there is exactly one distinct real root, sometimes called a double root
then there are no real roots. Rather, there are two distinct (non-real) complex roots.
is called the discriminant of the quadratic equation
Using roots, polynomial equation can be expressed as
Below the calculator