Quadratic inequalities
Quadratic inequalities
An inequality which contain terms in x² will usually have two solutions. For example,
x² < 4 (x x x = x² and -x x -x = x²)
Therefore:
(x²) < 4 and (-x)² < 4 (√ both sides)
x < 2 and -x < 2 (-1 both sides to move the minus from the variable to the number)
x < 2 and x < -2 (combine the solutions)
-2 < x < 2