\[\boxed{\text{130\ (130).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[\frac{1^{\backslash 1 + a}}{1 - a} + \frac{1^{\backslash 1 - a}}{1 + a} + \frac{2}{1 + a^{2}} +\]
\[+ \frac{4}{1 + a^{4}} + \frac{8}{1 + a^{8}} + \frac{16}{1 + a^{16}} =\]
\[= \frac{32}{1 - a^{32}}\]
\[Упростим\ левую\ часть\ \]
\[равенства:\]
\[\frac{1 + a + 1 - a}{1 - a^{2}} + \frac{2}{1 + a^{2}} + \frac{4}{1 + a^{4}} +\]
\[+ \frac{8}{1 + a^{8}} + \frac{16}{1 + a^{16}} = \frac{32}{1 - a^{32}}\]
\[\frac{2^{\backslash 1 + a^{2}}}{1 - a^{2}} + \frac{2^{\backslash 1 - a^{2}}}{1 + a^{2}} + \frac{4}{1 + a^{4}} +\]
\[+ \frac{8}{1 + a^{8}} + \frac{16}{1 + a^{16}} = \frac{32}{1 - a^{32}}\]
\[\frac{4^{\backslash 1 + a^{4}}}{1 - a^{4}} + \frac{4^{\backslash 1 - a^{4}}}{1 + a^{4}} + \frac{8}{1 + a^{8}} +\]
\[+ \frac{16}{1 + a^{16}} = \frac{32}{1 - a^{32}}\]
\[\frac{8^{\backslash 1 + a^{8}}}{1 - a^{8}} + \frac{8^{\backslash 1 - a^{8}}}{1 + a^{8}} + \frac{16}{1 + a^{16}} =\]
\[= \frac{32}{1 - a^{32}}\]
\[\frac{16^{\backslash 1 + a^{16}}}{1 - a^{16}} + \frac{16^{\backslash 1 - a^{16}}}{1 + a^{16}} = \frac{32}{1 - a^{32}}\]
\[\frac{32}{1 - a^{32}} = \frac{32}{1 - a^{32}}\text{.\ }\]
\[\boxed{\text{130.}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[1)\ \frac{a - c}{b + c} + \frac{b - a}{a + c} + \frac{c - b}{a + b} = 1\]
\[Прибавим\ к\ обеим\ частям\ \]
\[равенства\ 3:\]
\[\frac{a - c}{b + c} + \frac{b - a}{a + c} + \frac{c - b}{a + b} + 3 = 1 + 3\]
\[\frac{a - c}{b + c} + 1 + \frac{b - a}{a + c} + 1 + \frac{c - b}{a + b} +\]
\[+ 1 = 4\]
\[Преобразуем\ левую\ часть\ \]
\[равенства:\]
\[\frac{a - c}{b + c} + \frac{b - a}{a + c} + \frac{c - b}{a + b} = \frac{a - c}{b + c} +\]
\[+ 1^{\backslash b + c} + \frac{b - a}{a + c} + 1^{\backslash a + c} + \frac{c - b}{a + b} +\]
\[+ 1^{\backslash a + b} =\]
\[= \frac{a - c + b + c}{b + c} + \frac{b - a + a + c}{a + c} +\]
\[+ \frac{c - b + a + b}{a + b} =\]
\[= \frac{a + b}{b + c} + \frac{b + c}{a + c} + \frac{c + a}{a + b}.\]
\[Тогда:\]
\[\frac{a + b}{b + c} + \frac{b + c}{a + c} + \frac{c + a}{a + b} = 4.\ \]
\[Что\ и\ требовалось\ доказать.\]