Fundamental theorem of algebraFundamental theorem of algebraic K-theoryFundamental theorem of algebraic number theoryFundamental theorem of arithmeticFundamental theorem of calculusFundamental theorem ...
Fundamental lemma of calculus of variationsFundamental lemma of Langlands and ShelstadFundamental lemma of sieve theoryFeinstein's fundamental lemma (information theory)Fundamental lemma of interpolat ...
The fundamental theorem of a field of mathematics is the theorem considered central to that field. The naming of such a theorem is not necessarily based on how often it is used or the difficulty of it ...
