\[\ \frac{y + c}{c} \cdot \left( \frac{c^{\backslash y + c}}{y} - \frac{c^{\backslash y}}{y + c} \right) =\]
\[= \frac{y + c}{c} \cdot \left( \frac{c(y + c) - cy}{y(y + c)} \right) =\]
\[= \frac{y + c}{c} \cdot \left( \frac{cy + c^{2} - cy}{y(y + c)} \right) =\]
\[= \frac{(y + c)c²}{cy(y + c)} = \frac{c}{y}\]
\[y = - \frac{6}{x}\]
\[Область\ определения\ функции:\]
\[x \in ( - \infty;0) \cup (0; + \infty).\]
\[y > 0\ \ при\ \ x < 0.\]
\[\frac{x}{x + 2} - \frac{(x - 2)^{2}}{2} \cdot \left( \frac{1}{x^{2} - 4} + \frac{1}{x^{2} - 4x + 4} \right) =\]
\[= \frac{x}{x + 2} - \frac{(x - 2)^{2}}{2} \cdot \left( \frac{1^{\backslash x - 2}}{(x - 2)(x + 2)} + \frac{1^{\backslash x + 2}}{(x - 2)^{2}} \right) =\]
\[= \frac{x}{x + 2} - \frac{(x - 2)^{2}}{2} \cdot \frac{x - 2 + x + 2}{(x - 2)^{2}(x + 2)} =\]
\[= \frac{x}{x + 2} - \frac{(x - 2)^{2}}{2} \cdot \frac{2x}{(x - 2)^{2}(x + 2)}\]
\[= \frac{x}{x + 2} - \frac{x}{x + 2} = 0 - не\ зависит\ от\ x.\]
\[\frac{5b}{2^{\backslash 3 - 2b} - \frac{4}{3 - 2b}} = \frac{5b}{\frac{2 \cdot (3 - 2b) - 4}{3 - 2b}} =\]
\[= \frac{5b}{\frac{6 - 4b - 4}{3 - 2b}} = \frac{5b}{\frac{2 - 4b}{3 - 2b}} =\]
\[= \frac{5b \cdot (3 - 2b)}{2 \cdot (1 - 2b)} = \frac{15b - 10b^{2}}{2 - 4b}\]
\(2 - 4b \neq 0\ \ \ \ \ \ \ \ \ \ \ \ \ 3 - 2b \neq 0\)
\[2 \neq 4b\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 2b \neq 3\]
\[b \neq 0,5\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ b \neq 1,5\]
\[Выражение\ \ имеет\ смысл\ при\ b \neq 0,5;\ \ \]
\[b \neq 1,5.\]
\[\mathbf{\ }\frac{28b^{6}}{c³} \cdot \frac{c^{5}}{84b^{6}} = \frac{28b^{6}c^{5}}{84b^{6}c³} = \frac{c^{2}}{3}\]