Find $\lim _ { x \rightarrow + \infty } f ( x )$

Multiple Choice

Find $\lim _ { x \rightarrow + \infty } f ( x )$ and $\lim _ { x \rightarrow - \infty } f ( x )$ .If the limiting value is infinite indicate whether it is + $\infty$ or - $\infty$ . $f ( x ) = \frac { 4 - 2 x ^ { 3 } } { 6 x ^ { 3 } - 6 x + 1 }$

A) + $\infty$ ،- $\infty$
B) - $\infty$ ، + $\infty$
C) $- \frac { 1 } { 3 }$ , $- \frac { 1 } { 3 }$
D) $- \frac { 1 } { 3 }$ , $\frac { 1 } { 3 }$