Question

Упростите выражение:(c/d-d/c)7cd/c-d

Answer 1

$1) \frac{c}{d} - \frac{d}{c} = \frac{c^2-d^2}{cd}$

2) $\frac{c^2-d^2}{cd} * \frac{7cd}{c-d} = \frac{(c-d)(c+d)}{cd} * \frac{7cd}{c-d} =7(c+d)$