Polynomials

A monomial is formed by the product of numbers and letters or variables (with powers). A polynomial is the addition or subtraction of monomials. If we only have two monomials, we call it binomial and if we have three, we call it trinomial.

The degree of a variable is the index of its power and the degree of the monomial is the addition of the degrees of its variables. The degree of a polynomial is the biggest degree of its monomials.

Examples:

· 3x + y is a binomial of degree 1

· x² – 3x + 2 is a trinomial of degree 2

· a + 3b – 5ab + 8abc is a polynomial of degree 3

Exercise: decide whether they are polynomials or not and if they are classify them:

a) x²y + 5x²y²

b) 5x/3 + 2xy +7/3

c) 3/x +2x²

Solutions: a) Binomial of degree 4; b) trinomial of degree 2; c) it is not a polynomial