Let's say that x is a variable that can take any real value.

__Definition __

**A monomial
of x is called every expression of the form ,
where a is a real number and n a positive integer. Every real number is
also called a monomial.**

__Definition__

**A polynomial of x is called any
expression of the form where**

**Polynomials of the form ,
that is, non zero numbers are called polynomials of degree 0.**
**A polynomial all of whose coefficients
are equal to 0 is called an identically vanishing polynomial and is replaced
by 0. No degree is attributed to identically vanishing polynomials.**

For example:

- is a polynomial of degree 3.
- 2 is a polynomial of degree 0.

p is called a

Thus, for the polynomials , ,

we have f( -1 ) = 0, g( i ) = -2, h( 0
) = 2