連続関数の平均値の近似公式とその誤差について

Abstract

Let f(x) be continuous on the interval [a, b]. The mean value M(f) of f(x) on [a, b] is defined as follows : [numerical formula] where we denote by F(x) the primitive function of f(x). In the case when F(x) is unknown, we must calculate Ad (f) by the aid of so-called approximate formulas. In this paper, we shall obtain first an asymptotic expansion of the mean value M(f) with the terms of Riemann's quadrature by parts and next its end-points correction formula. We remark that the celebrated Euler-Maclaurin's summation formula is an immediate consequence of our asymptotic expansion just obtained. Further we shall derive some approximate formulas of mean value based on the function-values at random points.