\[\boxed{\text{1258.\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\]
\[x^{- 2} + x^{- 1} + x\]
\[\textbf{а)}\ x^{- 2} + x^{- 1} + x =\]
\[= x\left( x^{- 3} + x^{- 2} + x^{0} \right) =\]
\[= x(x^{- 3} + x^{- 2} + 1)\]
\[\textbf{б)}\ x^{- 2} + x^{- 1} + x =\]
\[= x^{- 1}\left( x^{- 1} + x^{0} + x^{2} \right) =\]
\[= x^{- 1}(x^{- 1} + 1 + x^{2})\]
\[\textbf{в)}\ x^{- 2} + x^{- 1} + x =\]
\[= x^{- 2}\left( x^{0} + x + x^{3} \right) =\]
\[= x^{- 2}(1 + x + x^{3})\]