Archimedes' Lemma
Also known as the continuity axiom, this Eudoxus 
(Boyer 1968).It states that, given two magnitudes having a ratio, one can find a multiple of either which will exceed the other. Thisprinciple was the basis for the Archimedes invented to solve problems of Area and Volume.
References
Boyer, C. B. A History of Mathematics. New York: Wiley, p. 100, 1968.
- Diagonals Problem
- Diagram
- Diameter
- Diameter (General)
- Diameter (Graph)
- Diamond
- Dice
- Dichroic Polynomial
- Dido's Problem
- Diesis
- Diffeomorphism
- Difference
- Difference Equation
- Trigonometry Values Pi/4
- Trigonometry Values Pi/5
- Trigonometry Values Pi/6
- Trigonometry Values Pi/7
- Trigonometry Values Pi/8
- Trigonometry Values Pi/9
- Trigyrate Rhombicosidodecahedron
- Trihedron
- Trilinear Coordinates
- Trilinear Line
- Trilinear Polar
- Trillion