Chapter 2.5, Problem 40E

Horizontal asymptotes Determine $\underset{x\to \infty }{\lim }f\left(x\right)$ and $\underset{x\to -\infty }{\lim }f\left(x\right)$ for the following functions Then give the horizontal asymptotes of f (if any).

40.     $f\left(x\right)=\frac{12x^8-3}{3x^8-2x^7}$