Question

7класс, сократить дроби: а) 7х^4у 49ху^3 б) 8а^2b^3(a+b) 20ab^2(a+b) в) ma^2-m^2a m^2-ma г) 4-d^2 3d+6 д) m^2+2mn+n^2 (m+n)^2 е) х^2+x x^3+1

Answer 1

$\frac{7x^4y}{49xy^3}= \frac{x^3}{7y^2}$
$\frac{8a^2b^3(a+b)}{20ab^2(a+b)} = \frac{2ab}{5}$
$\frac{ma^2-m^2a}{m^2-ma} = \frac{-ma(m-a)}{m(m-a)} =-a$
$\frac{4-d^2}{3d+6}= \frac{(2-d)(2+d)}{3(d+2)} = \frac{2-d}{3}$
$\frac{m^2+2mn+n^2}{(m+n)^2} = \frac{(m+n)^2}{(m+n)^2} =1$
$\frac{x^2+x}{x^3+1} = \frac{x(x+1)}{(x+1)(x^2-x+1)}= \frac{x}{x^2-x+1}$