Ответ Автор - hlopushinairina (5y⁹-5y⁷)/(y⁸-2y⁷+y⁶)=5y⁷·(y²-1)/[y⁶·(y²-2y+1)]=5y(y²-1)/(y-1)²==5y·(y-1)·(y+1)/(y-1)²=5y·(y+1)/(y-1);