L'Hopital's rule

L'Ho·​pi·​tal's rule | \ ˌlō-pē-ˈtälz- How to pronounce L'Hopital's rule (audio) \
variants: or L'Hospital's rule

Definition of L'Hopital's rule

: a theorem in calculus: if at a given point two functions have an infinite limit or zero as a limit and are both differentiable in a neighborhood of this point then the limit of the quotient of the functions is equal to the limit of the quotient of their derivatives provided that this limit exists

First Known Use of L'Hopital's rule

1918, in the meaning defined above

History and Etymology for L'Hopital's rule

Guillaume de l'Hôpital †1704 French mathematician

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The first known use of L'Hopital's rule was in 1918

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