The answer is:
"A polynomial is a monomial or the sum or difference of two or more monomials".
By definition, the terms of a Polynomial Function have the form ax^n, where "n" is a natural number.
To classify a polynomial, you must count the number of its terms. For example:
5x²-2x (This is a binomial, because it is formed by two terms).
x³-3x+1 (This is a trinomial, because it has three terms):
To identify the degree of a polynomial, you must see the term which has the highest exponent. For example, the degree of following polynomial is 2.
4x²-x+3
The degree of this polynomial is 3:
x³+2x²-x+10