номер 100 гдз 8 класс алгебра Муравин Муравин

1) k, n є N при n > k
a)\begin{equation}\frac{1}{k^{2}+kn}+\frac{1}{n^{2}+kn} \end{equation} \begin{equation}\frac{1}{k\left ( k+n \right )}+\frac{1}{n\left ( n+k \right )}= \end{equation} \begin{equation}=\frac{n+k}{nk\left ( k+n \right )}=\frac{1}{nk} \end{equation} б)\begin{equation}\frac{1}{kn-k^{2}}-\frac{1}{n^{2}-kn} \end{equation} \begin{equation}\frac{1}{k\left ( n-k \right )}-\frac{1}{n\left ( n-k \right )}= \end{equation} \begin{equation}=\frac{n-k}{nk\left ( n-k \right )}=\frac{1}{nk} \end{equation} 2)\begin{equation}\frac{1}{35}+\frac{1}{44}=\frac{44+35}{44\cdot 35}=\frac{79}{44\cdot 35} \end{equation} \begin{equation}\frac{1}{35}-\frac{1}{44}=\frac{44-35}{35\cdot 44}=\frac{9}{35\cdot 44} \end{equation}