Самостоятельная работа «Умножение и деление рациональных дробей»

1) $\frac{5a-c}{8p} \cdot \frac{7}{5a-c} = \frac{7}{8p}$ 2) $\frac{a-2b}{x+c} \cdot \frac{3(x+c)}{5(a-2b)} = \frac{3}{5}$ 3) $\frac{a(a-2b)}{x(x+y)} \cdot \frac{x+y}{a-2b} = \frac{a}{x}$ 4) $\frac{b(a-2b)}{y(x+y)} \cdot \frac{5(y+x)}{b(2b-a)} = -\frac{5}{y}$ 5) $\frac{7a^{15}}{b^7} \cdot \frac{b^8}{21a^{16}} = \frac{b}{3a}$ 6) $\frac{8a+3b}{3c} \cdot \frac{3n}{3b+8a} = \frac{n}{c}$ 7) $\frac{a-2b}{m+3n} \cdot \frac{3n+m}{2b-a} = -1$ 8) $\frac{(x-c)(x+c)}{a-b} \cdot \frac{(a-b)(a+b)}{x+c} = (x-c)(a+b)$ 9) $\frac{(a-b)(a+b)}{(a-x)^2} \cdot \frac{a-x}{a-b} = \frac{a+b}{a-x}$ 10) $\frac{5a+3x}{2x} \cdot 3x = \frac{3(5a+3x)}{2} = \frac{15a+9x}{2} = 7.5a+4.5x$ 11) $\frac{8y}{(y-a)(y+a)} \cdot (y+a) = \frac{8y}{y-a}$ 12) $\frac{3a^2}{5b-3c} \cdot \frac{1}{6a} = \frac{a}{2(5b-3c)} = \frac{a}{10b-6c}$ 13) $\frac{(m-2n)(m+2n)}{m+n} \cdot \frac{1}{m-2n} = \frac{m+2n}{m+n}$ 14) $\frac{(p-2c)(p+2c)}{(a+5b)^2} \cdot \frac{a^2-25b^2}{2c-p} = \frac{(p-2c)(p+2c)}{(a+5b)^2} \cdot \frac{(a-5b)(a+5b)}{-(p-2c)} = -\frac{(p+2c)(a-5b)}{a+5b} = \frac{(p+2c)(5b-a)}{a+5b}$