\[\boxed{\text{782\ (782).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\frac{a + b}{a^{2} + ab + b^{2}} \cdot \frac{a^{3} - b^{3}}{b^{2} - a^{2}}\ :\left( 1 - \frac{1 + b}{b} \right) =\]
\[= - 1\ :\left( - \frac{1}{b} \right) = b\]
\[1)\ \frac{a + b}{a^{2} + ab + b^{2}} \cdot \frac{a^{3} - b^{3}}{b^{2} - a^{2}} =\]
\[= \frac{a - b}{b - a} = - 1;\]
\[2)1 - \frac{1 + b}{b} = \frac{b - 1 - b}{b} = - \frac{1}{b}\text{.\ }\]