Помогите упростить выражения:

1)(36-y)/(y-8) *[y/(y-6) -2y/(y-12y+36)] + 12y/(y-6)=-y

y/(y-6) -2y/(y-6)=(y-6y-2y)/(y-6)=y(y-8)/(y-6)
(36-y)/(y-8) *y(y-8)/(y-6)=(6-y)(6+y)*y*(y-8)/(y-8)*(6-y)=y(6+y)/(6-y)
y(6+y)/(6-y)+12y/(y-6)=(6y+y-12y)/(6-y)=y(y-6)/(6-y)=-y

2)[3x/(x-4) -6x/(x-8x+16)]:(x-6)/(16-x) +24x/(x-4)=-3x

3x/(x-4) -6x/(x-4)=(3x-12x-6x)/(x-4)=3x(x-6)/(x-4)
3x(x-6)/(x-4): (x-6)/(16-x)=3x(x-6)/(4-x)*(4-x)(4+x)/(x-6)=3x(4+x)/(4-x)
3x(4+x)/(4-x)+24x/(x-4)=(12x+3x-24x)/(4-x)=3x(x-4)/(4-x)=-3x

3)[(a+b)/(b-a) -(b-a)/(b+a) -4a/(a-b)] : [a/(b-ab) +(a-b)/b+2/b]=(b+a)/(b-ab)

(a+b)/(b-a) -(b-a)/(b+a) -4a/(a-b)=(a+2ab+b-b+2ab-a+4a)/(b-a)=
=4a(a+b)/(b-a)
a/b(b-a) +(a-b)/b +2/b=(a-b+2ab-a+2b-ab)/b(b-a)=(b+ab)/b(b-a)=
=b(b+a)/b(b-a)=(b+a)/(b-ab)