2) $$\frac{4d+7}{7d} - \frac{d-6}{6d} = \frac{6(4d+7)}{42d} - \frac{7(d-6)}{42d} = \frac{24d+42-7d+42}{42d} = \frac{17d+84}{42d}$$
Ответ: $$\frac{17d+84}{42d}$$