“Fermat's”

The following 2 entries include the term Fermat's.

Fermat's last theorem

noun

: a theorem in number theory: the equation xⁿ + yⁿ = zⁿ has no solutions when x, y, z, and n are all positive integers and n is greater than 2

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Fermat's principle

noun

: a statement in optics: the path actually followed by a ray of light undergoing reflection or refraction is one of either minimum or maximum time as compared with adjacent arbitrary paths except for reflection or refraction at an aplanatic surface or passage through an aplanatic lens for which the time is constant

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