Square of a Binomial
The Square of a binomial looks like
Think Pythagorean Theorem for the reason.
To obtain the correct value we need to FOIL. The meaning of is
General Rule:
Example:
Use this pattern to simply convert the square of a binomial without actually FOILing.
Difference of Squares
This is called the \textbf{difference of squares} because the is squared, the
is also squared, and they are subtracted (difference).
This happens when you multiply 2 special binomials.
Example: Foil the following
Notice the middle terms cancel out. The first term
and last term
are both perfect squares. They have subtraction in between them, hence the “difference” in difference of squares.
Thus, our answer is