obtain polynomials close optimal one expanding given function terms chebyshev polynomials cutting expansion desired degree similar fourier analysis function using chebyshev polynomials instead usual trigonometric functions one calculates coefficients chebyshev expansion function math f x sim sum infty c x math cuts series math n math term one gets ''n'' span style padding left em th span degree polynomial approximating ''f'' ''x'' reason polynomial nearly optimal functions rapidly converging power series
Formal science Mathematics Applied mathematics Approximation theory