7-m 3+ 2m B) = 6m³ 2m²

Решение:

$$\frac{7-m}{6m^3} - \frac{3+2m}{2m^2} = \frac{7-m-3m(3+2m)}{6m^3} = \frac{7-m-9m-6m^2}{6m^3} = \frac{-6m^2-10m+7}{6m^3}$$

Ответ:

$$\frac{-6m^2-10m+7}{6m^3}$$