\[\boxed{\text{1187.\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\]
\[\textbf{а)}\frac{3}{b^{2}} = 3b^{- 2}\]
\[\textbf{б)}\frac{x}{y} = xy^{- 1}\]
\[\textbf{в)}\frac{2a^{8}}{c^{5}} = 2a^{8}c^{- 5}\]
\[\textbf{г)}\frac{a^{5}}{7b^{3}} = a^{5}\left( 7b^{3} \right)^{- 1}\]
\[\textbf{д)}\frac{1}{x^{2}y^{3}} = x^{- 2}y^{- 3}\]
\[\textbf{е)}\ \frac{(a + b)^{2}}{b^{4}c^{4}} = (a + b)^{2} \cdot\]
\[\cdot b^{- 4} \cdot c^{- 4}\]
\[\textbf{ж)}\frac{2a}{(a - 2)^{2}} = 2a(a - 2)^{- 2}\]
\[\textbf{з)}\ \frac{(c + b)^{5}}{2 \cdot (a - b)^{4}} = (c + b)^{5} \cdot\]
\[\cdot \left( 2 \cdot (a - b)^{4} \right)^{- 1}\]