00:01
Being asked to factor the binomial x to the 4 minus 81.
00:03
Well, you should always start by looking for greatest common factor first, but in this case, there isn't one.
00:09
So we have to determine, because it's a binomial, whether this is the difference of squares or the sum of difference of cubes.
00:15
Well, in this case, i know that both of our terms are perfect squares, because when we square x squared, we get x to the 4, and 9 squared is 81.
00:23
So this is a difference of squares problem.
00:25
So remember, we have a special formula to help us factor it.
00:28
It says if we have a squared minus b squared, it will factor to a plus b times a minus b.
00:36
Well, in this case, a is our first terms base, which is x squared, and b is the base of the second term, which is nine...