signum function
The name and notation come from the fact that the value of the function depends on the sign of x. This notation is also used for the parity of permutations, that is,
- arccos
- arccosh
- Archimedean property
- Archimedean solid
- Archimedean spiral
- Archimedes
- Archimedes' constant
- Archimedes' method
- arc length
- are
- area
- area of a surface of revolution
- area under a curve
- arg
- Argand diagram
- Argand, Jean Robert
- argument
- argument
- Aristarchus of Samos
- Aristotelian logic
- Aristotle
- arithmetic
- arithmetic function
- arithmetic-geometric mean
- arithmetic-geometric mean inequality