Question

Помогите пожалуйста. ​

Answer 1

$\frac{5y^2}{1-y^2}:(1-\frac{1}{1-y})=\frac{5y^2}{(1-y)(1+y)}:\frac{1-y-1}{1-y}=\\\\\frac{5y^2}{(1-y)(1+y)}:\frac{-y}{1-y}=\frac{5y^2}{(1-y)(1+y)}\cdot\frac{1-y}{-y}=\frac{-5y}{1+y}$