Polynomial Definitions
- A term is a number or the product of a number & variables raised to powers.
- The (numerical) coefficient is the numerical factor of a term.
- A polynomial is a finite sum of terms of the form axn, where a is a real number and n is a whole number (0, 1, 2, …). (poly = many, nomial = name or term, so “many terms”)
- A monomial is a polynomial with exactly 1 term. (mono = one)
- A binomial is a polynomial with exactly 2 terms. (bi = two)
- A trinomial is a polynomial with exactly 3 terms. (tri = three)
- The degree of a term is the sum of the exponents of the variables in the term.
- Example: the degree of 6x is 1, the degree of 3xy2 is 3, and the degree of 7 is 0, since 7 = 7x0.
- The degree of a polynomial is the greatest degree of its terms,
- Example the degree of 6x + 3xy2 – 7 is 3.
- To evaluate a polynomial substitute the given value(s) for the corresponding variable(s). When a polynomial is a function and want to evaluate we replace the independent variable with the given value.
- Examples:
- f(x) = 6x – 4, find f(3)
- f(3) = 6(3) – 4
- f(3) = 18 – 4
- f(3) = 14
- 2x3 – 3x + 4, evaluate when x = -2
- 2(-2)3 – 3(-2) + 4
- 2*-8 - -6 + 4
- -16 + 6 + 4
- -10 + 4
- -6