Выполни действия 1) \cfrac{7m+n}{m^{2}-n^{2}}+\cfrac{1}{m+n}=\cfrac{7m+n}{(m+n)(m-n)}+\cfrac{1}{m+n}= . 2) \cfrac{4}{x^2-4y^{2}}-\cfrac{1}{xy-2y^{2}}= . 3) \cfrac{b}{b+9}-\cfrac{b^{2}}{b^{2}+18b+81}=\cfrac{b}{b+9}-\cfrac{b^{2}}{(b+9)^{2}}= . 4) \cfrac{16y^{2}}{9x^{2}-24xy+16y^{2}}-\cfrac{4y}{3x-4y}= .
Задание

Выполни действия

  1. \(\cfrac{7m+n}{m^{2}-n^{2}}+\cfrac{1}{m+n}=\cfrac{7m+n}{(m+n)(m-n)}+\cfrac{1}{m+n}=\) [ ].

  2. \(\cfrac{4}{x^2-4y^{2}}-\cfrac{1}{xy-2y^{2}}=\) [ ].

  3. \(\cfrac{b}{b+9}-\cfrac{b^{2}}{b^{2}+18b+81}=\cfrac{b}{b+9}-\cfrac{b^{2}}{(b+9)^{2}}=\) [ ].

  4. \(\cfrac{16y^{2}}{9x^{2}-24xy+16y^{2}}-\cfrac{4y}{3x-4y}=\) [ ].