6 / 2(1+2)
By the order of operations......the division of 6 / 2 occurs first.....= 3
So
3 ( 1 + 2) =
3 ( 3) = 9
But
6 / [ 2 ( 1 + 2) ] =
6 / [ 2 (3) ] =
6 / 6 =
1
This points up the importance of parentheses.............and the lack of their use often changes the nature of the problem.....!!!!!!