Chapter 5 Polynomials and Polynomial Functions - 5.2 Evaluate and Graph Polynomial Functions - 5.2 Exercises - Skill Practice - Page 341: 6

not polynomial

A polynomial function is in the form $a_nx^n+a_{n-1}x^{n-1}+...+a_1x+a_0$ where $a_n\ne0$, the coefficients are real, and $n$ is a non-negative integer. Then $a_n$ is the leading coefficient, and $n$ is the degree. Hence here the function is not a polynomial because negative powers of $x$ are not allowed.