Calculus
Advanced

L'Hôpital's Rule

Evaluates indeterminate limits 0/0 or ∞/∞.

Formula

lim⁡x→cf(x)g(x)=lim⁡x→cf′(x)g′(x)\lim_{x\to c}\frac{f(x)}{g(x)} = \lim_{x\to c}\frac{f'(x)}{g'(x)}

Variables

f, gFunctions
cLimit point

Example

lim(x→0) sin x / x = lim cos x / 1 = 1.

Did You Know?

L'Hôpital's rule was actually discovered by Johann Bernoulli — L'Hôpital just paid to publish it.

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