5.6. Упростите выражение: а) 12x⁵/55 : 6x²/5; б) 4/(3y³) · y⁸/18; в) 16/(5d³) : 12/d⁴; г) 36c¹²/49 · 7/(6c¹⁵).

а) \(\dfrac{12x^5}{55}:\dfrac{6x^2}{5}=\dfrac{12x^5}{55}\cdot\dfrac{5}{6x^2}=\dfrac{2x^3}{11}\).

б) \(\dfrac{4}{3y^3}\cdot\dfrac{y^8}{18}=\dfrac{2y^5}{27}\).

в) \(\dfrac{16}{5d^3}:\dfrac{12}{d^4}=\dfrac{16}{5d^3}\cdot\dfrac{d^4}{12}=\dfrac{4d}{15}\).

г) \(\dfrac{36c^{12}}{49}\cdot\dfrac{7}{6c^{15}}=\dfrac{6}{7c^3}\).