This week we started looking at solving Quadratic Inequalities in 1 variable.

In order to solve quadratic inequalities we need to find the zeroes of the functions. To find the zeroes of a function we need to factor.

For example;

we can factor that into; (x+4)(x-2)>0

the zeroes of the function are; -4 and 2

 

from finding the zeroes of the function we can determine what numbers x can be to make it positive or negative.

To find if what x needs to be, you place both the zeroes of the function on a number,one and substitute a number in x three time. One needs to be less than -4 (lowest zero pair)  another one needs to Ben more than 2 (greatest zero pair) and he third numbers needs to be in between -4 and 2. By solving the equations we can figure out what x has to be greater than and less than.

In this case  the solution for the inequality is; x<-4 and x>2