4. Берілген өрнектерді ықшамдаңдар: 1) 9x²/(5y³) : 27x⁵/(2y⁴) · 15/[4y(x−1)]; 2) 25a(b−1)/(3²d) : 5cd²/(27ab) : a³(b−1)/(c³d²); 3) 28p⁴/(5q³) · 15q²(p−2)/(7p²) : 3p²/(4q³); 4) 12x⁵y⁴/(13ab²) : 4xy²/(13a²b) : 3x²(y+3)/(ab).

1. \[\dfrac{9x^2}{5y^3}\cdot\dfrac{2y^4}{27x^5}\cdot\dfrac{15}{4y(x-1)}=\dfrac1{x^3(x-1)}.\]
2. \[\dfrac{25a(b-1)}{9d}\cdot\dfrac{27ab}{5cd^2}\cdot\dfrac{c^3d^2}{a^3(b-1)}=\dfrac{15bc^2}{a}.\]
3. \[\dfrac{28p^4}{5q^3}\cdot\dfrac{15q^2(p-2)}{7p^2}\cdot\dfrac{4q^3}{3p^2}=32q^2(p-2).\]
4. \[\dfrac{12x^5y^4}{13ab^2}\cdot\dfrac{13a^2b}{4xy^2}\cdot\dfrac{ab}{3x^2(y+3)}=\dfrac{a^2x^2y^2}{y+3}.\]

Жауап: 1) \(\dfrac1{x^3(x-1)}\); 2) \(\dfrac{15bc^2}{a}\); 3) \(32q^2(p-2)\); 4) \(\dfrac{a^2x^2y^2}{y+3}\).