Binary Operations

The word "operation" refers to a process performed on either a single element or several elements at once. Finding the negative of a real number, $-a$, needs just one input -- it is an unary operation. Finding the sum of two real numbers needs two inputs -- this is a binary operation. In general, an operation that combines $n$ elements at a time is called an $n$-ary operation, $n\in\mathbb N$. …