Chapter 3 Chebyshev Expansions - SIAM
https://siam.org/books/ot99/OT99SampleChapter.pdfChebyshev polynomials form a special class of polynomials especially suited for approximating other functions. They are widely used in many areas of numerical analysis: uniform approximation, least-squares approximation, numerical solution of ordinary and partial differential equations (the so-called spectral or pseudospectral methods), and so on.