Question

Помог те преобразовать

Answer 1

а) ((3a+1)/(3a-1) - (3a-1)/(3a+1)):4a/(15a+5) =

= (9a²+6a+1-9a²+6a-1)/((3a-1)(3a+1)) × (5(3a+1))/4a =

= (12a×5(3a+1))/((3a-1)(3a+1)×4a)=15/3a-1

б) y²/(x+1) ×(1-x²)/(y-1)-(1-xy²)/(y-1) =

= y²/(x+1) × ((1-x)(x+1))/(y-1) - (1-xy²)/(y-1) =

= (y²-xy²-1+xy²)/(y-1) =

= ((y-1)(y+1))/(y-1) = y+1