номер 79 гдз 8 класс алгебра Муравин Муравина

1)\begin{equation}\frac{a+b+2c}{abc} \end{equation} \begin{equation}\frac{a}{abc}+\frac{b}{abc}+\frac{2c}{abc}= \end{equation} \begin{equation}=\frac{1}{bc}+\frac{1}{ac}+\frac{2}{ab} \end{equation} 2)\begin{equation}\frac{3x+2y-6}{6xy} \end{equation} \begin{equation} \frac{3x}{6xy}+\frac{2y}{6xy}-\frac{6}{6xy}= \end{equation} \begin{equation}=\frac{1}{2y}+\frac{1}{3x}-\frac{1}{xy} \end{equation} 3)\begin{equation}\frac{d^{2}-4dc+3c^{2}}{6dc} \end{equation} \begin{equation}\frac{d^{2}}{6dc}-\frac{4dc}{6dc}+\frac{3c^{2}}{6dc}= \end{equation} \begin{equation}=\frac{d}{6c}-\frac{2}{3}+\frac{c}{2d} \end{equation} 4)\begin{equation}\frac{n^{2}+15kn-10k^{2}}{5k^{2}n^{2}} \end{equation} \begin{equation}\frac{n^{2}}{5k^{2}n^{2}}+\frac{15kn}{5k^{2}n^{2}}-\frac{10k^{2}}{5k^{2}n^{2}}= \end{equation} \begin{equation}=\frac{1}{5k^{2}}+\frac{3}{kn}-\frac{2}{n^{2}} \end{equation} 5)\begin{equation}\frac{\left ( x^{2}-y \right )^{2}}{x^{3}} \end{equation} \begin{equation}\frac{x^{4}-2x^{2}y+y^{2}}{x^{3}}= \end{equation} \begin{equation}=\frac{x^{4}}{x^{3}}-\frac{2x^{2}y}{x^{3}}+\frac{y^{2}}{x^{3}}= \end{equation} \begin{equation}=x-\frac{2y}{x}+\frac{y^{2}}{x^{3}} \end{equation} 6)\begin{equation}\frac{\left ( a-b \right )^{3}}{b^{2}}= \end{equation} \begin{equation}=\frac{a^{3}-3a^{2}b+3ab^{2}-b^{3}}{b^{2}}= \end{equation} \begin{equation}=\frac{a^{3}}{b^{2}}-\frac{3a^{2}b}{b^{2}}+\frac{3ab^{2}}{b^{2}}-\frac{b^{3}}{b^{2}}= \end{equation} \begin{equation}=\frac{a^{3}}{b^{2}}-\frac{3a^{2}}{b}+3a-b \end{equation}