ISSN : 1226-0657
[1] Show that ∫<TEX>$\_$</TEX>0/<TEX>$\^$</TEX>1/ [∫<TEX>$\_$</TEX>0/<TEX>$\^$</TEX>1/ f(<TEX>$\chi$</TEX>,y)dy] d<TEX>$\chi$</TEX> = ∫<TEX>$\_$</TEX>0/<TEX>$\^$</TEX>1/[∫<TEX>$\_$</TEX>0/<TEX>$\^$</TEX>1/ f(<TEX>$\chi$</TEX>,y)d<TEX>$\chi$</TEX>] Counterexample: If pk denotes the k-th prime number, let S(pk) = (equation omitted), let S = ∪<TEX>$\_$</TEX>k=1/<TEX>$\^$</TEX><TEX>$\infty$</TEX>/ S(pk), and let Q = [0, 1]<TEX>${\times}$</TEX>[0, 1]. Define f on Q as follows; f(<TEX>$\chi$</TEX>, y) = 0 (<TEX>$\chi$</TEX>, y)<TEX>$\in$</TEX>S, f(<TEX>$\chi$</TEX>, y) = 1 (<TEX>$\chi$</TEX>, y)<TEX>$\in$</TEX>Q - S.(omitted)