SECTION 6.2 THE QUADRATIC FORMULA AND THE DISCRIMINANT

Quadratic Formula:

The solutions of the quadratic equation with real coefficients a, b, and c, when a ¹ 0, are

The is called the discriminant.

If the discriminant > 0, there will be 2 distinct real solutions to the equation .

If the discriminant = 0, there will be 1 distinct real solution (double root) to the equation .

If the discriminant < 0, there will be no real solutions.

 

EXAMPLES:

1.

   

 

2.

   

3.

   

Since we cannot take the square root of -8 in the real number system, there is no real solution to this equation.