l'Hospital's rule

Topic Notes
Remember that one tricky Limits section that required intense algebraic manipulation to avoid getting 0/0 or infinity/infinity limits? We will now revisit it again, but with the knowledge of derivatives. In this section, we will learn how derivatives enable us to efficiently evaluate the limits of a function using the "L'Hospital's rule".
Note *l'Hôpital's Rule applies to 2 types of indeterminate forms:

type 00\frac{0}{0} (that is, lim⁡\limx →c c f(x)=0f(x)=0 and lim⁡\limx →c cg(x)=0g(x)=0)
or
type ∞∞\frac{\infty}{\infty} (that is, lim⁡\limx →c c f(x)=±∞f(x)=\pm \infty and lim⁡\limx →c cg(x)=±∞g(x)=\pm \infty)

Then according to l'Hôpital's Rule: lim⁡\limx →c c f(x)g(x)=\frac{f(x)}{g(x)}= lim⁡\limx →c c f′(x)g′(x)\frac{f'(x)}{g'(x)}
Basic Concepts