a.Ta có: 2|x| + 3|1-x| - |x-3| =0
2x + 3 - 3x - x +3 =0
-2x + 6 =0
-2x =-6
x =3
b.Ta có:4|3x-1| + |x| - 2|x-5| +7|x-3| =12
12x-4 + x -2(x-5) + 7x - 3 =12
12x-4+ x - 2x +10 + 7x - 3=12
18x + 3 =12
18x =12-3
18x =9
x =1/2
a. 2 |x |+ 3 | 1- x| - 5 | x - 3= 0
2 x + 3 - 3 x - x + 3 = 0
-2x + 6 = 0
- 2 x = - 6
x = 3