f (x) = 8x^3 - 12x

What is the question? You have defined a function but not said what you want to do with it.

Apologies for the confusion. To clarify, I can help you with various questions related to the given function f(x) = 8x^3 - 12x. This can include finding the value of the function at a particular x-coordinate, determining the behavior of the function, obtaining the x-intercepts, finding critical points, and performing other relevant calculations or analyses. Please let me know what specific question or task you would like assistance with.