Examples for the two binomials are
and their product is
. \ \
The product a sum and a difference formula:
.

.
The above result is called square binomial.
Examples for the two binomials are
and their product is
. \ \
The square of a sum formula:
.


The above result is not a binomial and it is called square trinomial.
The two binomials are
and their product is
,
The two binomials are
and their product is
.