Упр.5.29 ГДЗ Мордкович 8 класс (Алгебра)

б) 17x2y/5a:(-34xy2/25a2);
в) -35ax2/12b2y*8ab/21xy;
г) (-27c3/4b2):(-45c5/32b).

1. а)

   $$\left(-\frac{18a^3}{11b^3}\right)\cdot\left(-\frac{22b^4}{9a^2}\right) =\frac{18\cdot 22\cdot a^3b^4}{11\cdot 9\cdot b^3a^2}$$
   $$=\frac{18\cdot 22}{11\cdot 9}\cdot ab =4ab.$$

2. б)

   $$\frac{17x^2y}{5a}:\left(-\frac{34xy^2}{25a^2}\right) =\frac{17x^2y}{5a}\cdot\left(-\frac{25a^2}{34xy^2}\right)$$
   $$=-\frac{17\cdot 25\cdot x^2ya^2}{5\cdot 34\cdot axy^2} =-\frac{5ax}{2y}.$$

3. в)

   $$-\frac{35ax^2}{12b^2y}\cdot\frac{8ab}{21xy} =-\frac{35\cdot 8\cdot a^2x^2b}{12\cdot 21\cdot b^2x y^2}$$
   $$=-\frac{10a^2x}{9by^2}.$$

4. г)

   $$\left(-\frac{27c^3}{4b^2}\right):\left(-\frac{45c^5}{32b}\right) =\frac{27c^3}{4b^2}\cdot\frac{32b}{45c^5}$$
   $$=\frac{27\cdot 32}{4\cdot 45}\cdot\frac{1}{bc^2} =\frac{24}{5bc^2}.$$

Ответ

а) $$4ab$$; б) $$-\frac{5ax}{2y}$$; в) $$-\frac{10a^2x}{9by^2}$$; г) $$\frac{24}{5bc^2}$$.