Question 1046213
It's not clear what the original function is


IF the function is {{{f(x) = 8 - (x^3)/8}}}, then it is a polynomial. It's a degree 3 polynomial since the largest exponent is 3.


OR


IF the function is {{{f(x) = 8 - x^(3/8)^""}}} (notice how the exponent is 3/8), then it is NOT a polynomial because of the fractional exponent over the variable. 


<a href = "http://www.mathsisfun.com/algebra/polynomials.html">Here</a> is a good article to help determine what makes a polynomial or not.