How do you simplify #(x + 1)(x - 1)#?
Before we attempt to multiply this out, what do you notice about the binomial given?
If fits the difference of squares pattern
Now, every product of binomials won't be in this form, but we can use FOIL (Firsts, Outsides, Insides, Lasts), which will work every time. This is the order we multiply in.
- Multiply the first terms:
- Multiply the outside terms:
- Multiply the inside terms:
- Multiply the last term:
This is equal to
The middle terms cancel, and we're left with
Remember, FOIL will work every time, but if we see a product of binomials of the form
Hope this helps!