(3x-4)/(x-2)(x-1)=a/x-1 +b/x-2
(3x-4)/(x-2)(x-1)=[a(x-2)+b(x-1)]/(x-1)(x-2)
(3x-4)/(x-2)(x-1)=[(a+b)x-(2a+b)]/(x-1)(x-2)
a+b=3
2a+b=4
a=1
b=2