А) 4а^2b/(2a-3)^2-9b/(3-2a)^2=а) 4а^2b/(2a-3)^2-9b/(2a-3)^2=
(4а^2b-9b)/(2a-3)^2=b(4а^2-9)/(2a-3)^2=(b(2a-3)(2a+3))/(2a-3)^2=(b(2a+3))/(2a-3)
b) x^2/(x-3y)^3+9y^2/(3y-x)^3=x^2/(x-3y)^3-9y^2/(x-3y)^3=(x^2-9y²)/(x-3y)^3=
(x-3y)(x+3y)/(x-3y)^3=(x+3y)/(x-3y)^2
c) (yx^2+16/(y-1)(x-4))-(16y+x^2/(xy-x-4y+4))=(yx^2+16/(y-1)(x-4))-(16y+x^2/(y-1)(x-4))=
(yx^2+16-16y-x^2)/((y-1)(x-4))=((y-1)(x²-16))/((y-1)(x-4))=(x²-16)/(x-4)=
((x-4)(x+4))/(x-4)=x+4