Условие:
Упростите выражение:
1) (3y^2-10y+8)/(4y^2-36)*(y-3)/(y-2)+(0,25-y)/(y+3);
2) ((y-1)/(5y^2-16y+3)-3/(y^2-9))∶(y-13)/(2y^3-18y);
3) (6x/(x^2-x-2)+9/(x^2-4))∶(2x+1)/(x^2+3x+2)-(x+13)/(x-2).