Watch these videos and take notes. In the first example, the difference of two squares formula is applied twice in order to factor the expression completely: once to the original polynomial, and then to the new binomial factor. The second is an example of an interesting polynomial that can be attempted to be factored either by using the difference of two squares or difference of two cubes formulas. Whichever one you choose, the resultant factors can still be factored further using another special binomial factoring formula. In this video, the difference of two squares formula is used first. As an exercise, try an alternative method (e.g. applying difference of two cubes first) and try to show that the results will in fact be the same.