In this video we'll learn the most common FOIL situation, multiplying parentheses that each have two terms in them (a.k.a. binomials). Most students don't have too much trouble with the concept of FOIL; the most common mistake is forgetting one of the terms. First, Outside, Inside, Last is one way not to forget any terms, but I'll also show you my favorite graphical technique: drawing rainbows over and under to keep track.
FOIL On Bigger Problems (trinomials)
These problems have more terms than basic FOIL, but the same principals apply. One: everything in the first parentheses has to get multiplied by everything in the other parentheses. Two: don't forget anyone! Once again, my patented "draw rainbows everywhere" technique should make it easier to remember. NOTE: Some or all of the problems in this video might be more advanced that what your class is doing, so if you start getting scared, hit stop!
If you do not have an account, you should get one, because it is awesome! You can save a playlist for each test or each chapter, and save your "greatest hits" into a "watch right before the final" list (not that we recommend cramming, but when in Rome...)