Polynomial Functions Basics
A polynomial function follows the form f(x) = aₙxⁿ + aₙ₋₁xⁿ⁻¹ + ... + a₁x + a₀, where the coefficients are real numbers and n is a positive integer. These functions create smooth curves with no breaks or gaps and are continuous for all real numbers.
The degree of a polynomial is its highest exponent, which determines its classification. For example, degree 0 is constant f(x)=2, degree 1 is linear f(x)=−3x+8, degree 2 is quadratic f(x)=5x2+4x−1, and degree 3 is cubic f(x)=−4x3+x2−x+7.
The end behavior of a polynomial depends on the power and coefficient of its leading term. For even powers with positive coefficients, both ends point upward (↗↗); with negative coefficients, both ends point downward (↘↘). For odd powers with positive coefficients, left end points down and right end points up (↘↗); with negative coefficients, left end points up and right end points down (↗↘).
🔍 Try This: Identify the degree and end behavior of f(x) = -2x³+5x-1. Since the highest power is 3 (odd) with a negative coefficient, the function will rise on the left and fall on the right.