For any polynomial, first check to see if it factors. Then you can set each factor equal to zero.
The three zeros are -1,1,3
Next plug in values in each interval between zeros to test whether its greater than 0.
Try x values: -2,0,2,4
x = -2 yields a negative result, the interval x< -1 is Not a solution.
x = 0 yields a positive result, the interval -1
x = 2 yields a negative result, the interval 1
x = 4 yields a positive result, the interval x>3 IS a solution
The three zeros are -1,1,3
Next plug in values in each interval between zeros to test whether its greater than 0.
Try x values: -2,0,2,4
x = -2 yields a negative result, the interval x< -1 is Not a solution.
x = 0 yields a positive result, the interval -1
x = 2 yields a negative result, the interval 1
x = 4 yields a positive result, the interval x>3 IS a solution