(1)=(9-3)b/3ab=2a
(2)=[x(x-2)-x(x+2)+3x-2]/(x^2-4)
=-(x+2)/(x+2)(x-2)
=-1/(x-2)
(3)=[(x+1)^2+(x+1)-3]/(x+1)(x-2)=1
(x+1)^2+(x+1)-3=(x+1)(x-2)
(x+1)^2-(x+1)(x-3)-3=0
4x+1=0
x=-1/4
(4)
x-1+2x+2=1
3x=0
x=0