##  [Approximation Theory](/approximation-theory) 

  ##  [Approximation Theory](https://puremath.quantumdictionary.io/approximation-theory-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The study of how functions or objects are approximated by simpler or more tractable families (for example polynomials, splines, or rational functions), together with quantitative measures of the approximation error and convergence behaviour in chosen norms or metrics.