**2 types**of indeterminate forms:

**type $\frac{0}{0}$**(that is, $\lim$

_{x →$c$}$f(x)=0$ and $\lim$

_{x →$c$}$g(x)=0$)

or

**type $\frac{\infty}{\infty}$**(that is, $\lim$

_{x →$c$}$f(x)=\pm \infty$ and $\lim$

_{x →$c$}$g(x)=\pm \infty$)

Then according to l'Hôpital's Rule: $\lim$

_{x →$c$}$\frac{f(x)}{g(x)}=$ $\lim$

_{x →$c$}$\frac{f'(x)}{g'(x)}$