Approximation theory
Appearance
Approximation theory is a field of mathematics which is concerned with approximating the values of a function. Usually, the approximation is only needed ffor a drange of values or domain. A good appeoximation will only have a small error in the dommain of interest.
There are different ways in which this approximation is done: comon ones are usungva combunation of simpler functions or using polynomials.