2[1-1/3(x-x+1/3)]=3[x/6-1/2(2x-10−7x3)].

问题描述:

2[1-

1
3
(x-
x+1
3
)]=3[
x
6
-
1
2
(2x-
10−7x
3
)].

去中括号得:2-

2
3
(x-
x+1
3
)=
x
2
-
3
2
(2x-
10−7x
3
),
去小括号得:2-
2
3
x+
2x+2
9
=
x
2
-3x+
10−7x
2

去分母得:36-12x+4x+4=9x-54x+90-63x,
移项合并得:100x=50,
化系数为1得:x=
1
2