| Line 3: | Line 3: | ||
\displaystyle\lim_{x\to\a}\frac{f(x)}{g(x)}=\displaystyle\lim_{x\to\a}\frac{f'(x)}{g'(x)} | \displaystyle\lim_{x\to\a}\frac{f(x)}{g(x)}=\displaystyle\lim_{x\to\a}\frac{f'(x)}{g'(x)} | ||
</math>, | </math>, | ||
| − | if the limis on the right exists (or is | + | if the limis on the right exists (or is positive or negative infinity). |
This is Elizabeth's favorite theorem. | This is Elizabeth's favorite theorem. | ||
Revision as of 09:16, 4 September 2008
Suppose that f(a)=g(a)=0 and that f and g are differentiable on an open interval I containing a. Suppose also that g'(x)/=0 on I if x/=a. Then $ \displaystyle\lim_{x\to\a}\frac{f(x)}{g(x)}=\displaystyle\lim_{x\to\a}\frac{f'(x)}{g'(x)} $, if the limis on the right exists (or is positive or negative infinity).
This is Elizabeth's favorite theorem.
