internal division
where 
is the vector from A to B. Alternatively E is the point 
of the way along from A to B. If A and B have position vectors a and b, from some origin, then the position vector of E is
sometimes referred to as the section formula. Compare external division.
- Thales of Miletus
- theorem
- Theorema Egregium
- theorem proving
- there exists
- theta function
- Thom, René Frédéric
- Thomson, William
- three-body problem
- three-door problem
- thrust
- tie
- tiling
- time
- time dilation
- time series
- Tn
- Tonelli's theorem
- tonne
- topological data analysis
- topological group
- topologically distinguishable
- topological space
- topological vector space
- topology