Exercise 39

Draw sketches of the curves $y=e^x$, $y=e^{-x}$, $y=\fe{\ln}{x}$, and $y=\frac{1}{x}$. Note the coordinates of any and all intercepts. This is something you should be able to do from memory/intuition. If you cannot already do so, spend some time reviewing whatever you need to review so that you can do so. Once you have the graphs drawn, fill in each of the blanks below and decide whether or not each limit exists. The appropriate symbol for some of the blanks is either $\infty$ or $-\infty$.

$\lim\limits_{x\to-\infty}\dfrac{1}{e^x}=\underline{\qquad}\,(\text{exists?})$