Question

Решите два седьмых задания по действиям

Answer 1

1) $\frac{n(m+n)}{m} \frac{n}{(m+n)} \frac{1}{mn} = \frac{n}{m^2}$

=9/(1/3)² = 9*9 = 81

2)$(\frac{1}{(1-x)(1+x)} - \frac{1}{(1-x)^2} ) \frac{(x-1)^2}{2} =\\ = \frac{1-x-1-x}{(1-x)^2(1+x)} \frac{(x-1)^2}{2} =\\ = \frac{-2x}{(1+x)} \frac{1}{2} = -\frac{x}{1+x}$

1,5/(1-1,5) = 1,5/(-0,5) = -3