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Proof of special case of l'Hôpital's rule

L'Hôpital's rule helps us find limits in the form limxcu(x)v(x) where direct substitution ends in the indeterminate forms 00 or .
The rule essentially says that if the limit limxcu(x)v(x) exists, then the two limits are equal:
The AP Calculus course doesn't require knowing the proof of this fact, but we believe that as long as a proof is accessible, there's always something to learn from it. In general, it's always good to require some kind of proof or justification for the theorems you learn.
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Proof of special case of l'Hôpital's ruleSee video transcript

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