Approximation theory

Approximation theory is a field of mathematics which is concerned with approximating the values of a function. Usually, the approximation is only needed for a range of values or domain. A good approximation will only have a small error in the domain of interest.

There are different ways in which this approximation is done: common ones are using a combination of simpler functions or using polynomials. 

 Related pages 
Curve fitting
Rounding
Taylor series

Further reading
 Trefethen, L. N. (2019). Approximation theory and approximation practice. Society for Industrial and Applied Mathematics.
Category:Mathematical approximation