Question

3x+y/y * (y/x - 3y/3x+y)
Решите пожалуйста (это дроби)

Answer 1

$dfrac{3x+y}ycdot bigg(dfrac yx-dfrac{3y}{3x+y}bigg)=\\\=dfrac{3x+y}ycdot ycdot bigg(dfrac 1x-dfrac{3}{3x+y}bigg)=\\\=dfrac{3x+y}1cdot bigg(dfrac 1x-dfrac{3}{3x+y}bigg)=\\\=dfrac{3x+y}1cdot dfrac {3x+y-3x}{x(3x+y)}=\\\=dfrac {3x+y-3x}{x}boldsymbol{=dfrac yx}$