In this case we may factor out one or more powers of x to begin the problem. Now we have a product of x and a quadratic polynomial equal to 0, so we have two simpler equations. The first equation is trivial to solve. The second equation may be solved by factoring. Factor by Grouping Example 14.
Group terms one and two, and also terms three and four.
Whenever we find a product equal to zero, we obtain two simpler equations. Quadratic in Form Example 15. This polynomial is not quadratic, it has degree four. However, it can be thought of as quadratic in x 2 . It might help you to actually substitute z for x 2 .