Usenet Newsgroups : rec.puzzles Hall of FameThe rec.puzzles Hall of Fame is a compilation of over 500 of the most popular puzzles that have been posted and discussed in the rec.puzzles newsgroup. In most cases a detailed solution has been provided. Many of these puzzles also appear in Braingle's own collection. |
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If f is integrable on (0,inf) and differentiable at 0, and a > 0, and:
inf f(x)
Int ---------------- dx is defined
0 x
show:
inf ( f(x) - f(ax) )
Int ---------------- dx = f(0) ln(a)
0 x
Solution
