Chứng minh với mọi số dương $\it{a},\,\it{b},\,\it{c}$ thỏa $\it{abc}= \it{1}$ thì:
$\frac{\it{a}}{\it{2}\,\it{a}^{\,\it{m}}+ 1}+ \frac{\it{b}}{\it{2}\,\it{b}^{\,\it{m}}+ 1}+ \frac{\it{c}}{\it{2}\,\it{c}^{\,\it{m}}+ 1}\leqq \it{1}$
$\lceil\,\,\frac{\it{9}}{\it{4}}\leqq \it{m}\leqq \frac{\it{15}}{\it{4}}\,\,\rfloor$