FOIL rule
Overview
Elementary algebra
Elementary algebra is a fundamental and relatively basic form of algebra taught to students who are presumed to have little or no formal knowledge of mathematics beyond arithmetic. It is typically taught in secondary school under the term algebra. The major difference between algebra and...
, FOIL is a mnemonic
Mnemonic
A mnemonic , or mnemonic device, is any learning technique that aids memory. To improve long term memory, mnemonic systems are used to make memorization easier. Commonly encountered mnemonics are often verbal, such as a very short poem or a special word used to help a person remember something,...
for the standard method of multiplying two binomial
Binomial
In algebra, a binomial is a polynomial with two terms —the sum of two monomials—often bound by parenthesis or brackets when operated upon...
s—hence the method may be referred to as the FOIL method. The word FOIL is an acronym for the four terms of the product:
- First (“first” terms of each binomial are multiplied together)
- Outer (“outside” terms are multiplied—that is, the first term of the first binomial and the second term of the second)
- Inner (“inside” terms are multiplied—second term of the first binomial and first term of the second)
- Last (“last” terms of each binomial are multiplied)
The general form is:
Note that
is both a “first” term and an “outer” term; 
is both a “last” and “inner” term, and so forth.
Unanswered Questions
