|x-1|-2|x-2|+3|x-3|=4
(1)x>=3
x-1-2(x-2)+3(x-3)=4
x-1-2x+4+3x-9=4
2z=10
x=5
(2)2<=x<3
x-1-2(x-2)-3(x-3)=4
x-1-2x+4-3x+9=4
-4x=-8
x=2
(3)1<=x<2
x-1+2(x-2)-3(x-3)=4
x-1+2x-4-3x+9=4
4=4
(4)x<1
-(x-1)+2(x-2)-3(x-3)=4
-x+1+2x-4-3x+9=4
-2x=-2
x=1
综述方程的解是x=5或1<=x<=2