GaussianQuadratureError[n, f, a, b] gives the leading term in the error of the elementary n-point Gaussian quadrature formula for the function f on an interval from a to b.
GaussianQuadratureError[n, f, a, b, prec] attempts to give a result with prec digits of precision.
The function f may be a pure function or a named function defined using Set or SetDelayed.
The error is given as a function of n, a and b multiplied by an mth derivative of the function f. The size of the error is bounded by the maximum of this expression over the interval from a to b.
