ABSTRACT
The expression on the r ight side of (4.6.2) is a R i e m a n n sum of the in tegra l fRn ip(u)Ae(u)du. Therefore A(an) tends to JRn (p(u)A@(u) du as h - » 0. F r o m the above considerat ion i t follows that
( A Y 0 Qx)if(x + y) - j (p(u)Ae(u) du.
