sphere
The interior of a sphere of radius r has volume 
, and the surface area equals 4πr2.
In topology, the n-dimensional sphere is denoted as Sn and is often identified with the unit sphere in Rn+1, that is,
The spheres described above are topologically S2.
- map projection
- marginal distribution
- Markov, Andrei Andreevich
- Markov chain
- martingale
- mass
- mass–energy equation
- matched‐pairs design
- matching
- material derivative
- mathematical biology
- mathematical induction
- mathematical model
- mathematical notation
- mathematics
- mathematics education
- matrix
- matrix game
- matrix groups
- matrix norm
- matrix of a linear map
- matrix of coefficients
- matrix of cofactors
- Maupertuis, Pierre‐Louis Moreau de
- maximal element