Ответ:

а) \(\dfrac{a(x-2)}{b(x-2)}=\dfrac{a}{b}\).

б) \(\dfrac{4(c+3)^2}{(c+3)^3}=\dfrac{4}{c+3}\).

в) \(\dfrac{5y(b-7)}{10(b-7)^2}=\dfrac{y}{2(b-7)}\).

г) \(\dfrac{p^3(q-1)^4}{p^6(q-1)^2}=\dfrac{(q-1)^2}{p^3}\).

Ответ: а) \(\dfrac{a}{b}\); б) \(\dfrac{4}{c+3}\); в) \(\dfrac{y}{2(b-7)}\); г) \(\dfrac{(q-1)^2}{p^3}\).