@@ bây giờ mới ngỡ ra
TH1:
2.|x-1| = 6
=> 2.(x-1) = 6
2x-2 = 6
2x = 6+2
x = 8
x = 8:2
x = 4
TH2:
2.|x-1| = 6
=> 2[-(x-1)] = 6
2.[-x+1] = 6
-2x+2 = 6
-2x = 6-2
-2x = 4
x = 4:(-2)
x = -2
=>\(\sqrt{4\left(X-1\right)^2}=6\Rightarrow4\left(X-1\right)^2=36\Rightarrow\left(X-1\right)^2=9\Rightarrow X-1=3\Rightarrow X=4\)
<=>2|x-1|=6
<=>|x-1|=6:2
<=>|x-1|=3
<=>x-1=3 hoặc x-1=-3
<=>x=3+1 hoặc x=-3+1
<=>x=4 hoặc x=-2