CPM Homework Help : PC3 Problem 13-21

Evaluate each the following limits.

$\lim \limits _ { x \rightarrow - \infty } \frac { 2 x } { x ^ { 3 } }$
Hint (a):
The dominant term is in the denominator.
Therefore as $x→−∞$ , the fraction gets closer to __.

$\lim \limits _ { x \rightarrow - \infty } \frac { \sqrt { x ^ { 2 } + 5 } } { 2 x }$
Hint (b):
The dominant term is $\left|x\right|$ in the numerator (square root of $x^{2}$ is $\left|x\right|$ ) and $2x$ in the denominator.