The FOIL method is an acronym for first , outer, inner and last. This is a way by which two binomials can easily be multiplied.
Take the binomials a + b and c + d
When the two are multiplied (a+b)(c+d), the result is given by ac + ad + bc + bd. Using the FOIL method to accomplish this, start by multiplying the first terms of the binomials, i.e. a and c, next multiply the outer terms a and d, this is followed by multiplying the inner terms b and c and finally the last terms or b and d are multiplied.
The FOIL method is used to remember the operations involved in multiplying two binomials: (a+b)(c+d) = ac + ad +bc + bd