0-1/2-括号3/4+括号5/6-2/3
(1)=0-1/2-(3/4+5/6)-2/3
=-6/12-(9/12+10/12)-8/12
=-6/12-19/12-8/12
=-33/12
=-11/4
(2)=0-1/2-(3/4)+(5/6)-2/3
=-6/12-9/12+10/12-8/12
=-15/12+10/12-8/12
=-5/12-8/12
=-13/12
0-1/2-括号3/4+括号5/6-2/3
=-1/2-(3/4+(5-4)/6)
=-1/2-(3/4+1/6)
=-1/2-(9+2)/12
=-1/2-11/12
=-6/12-11/12=-17/12
0-1/2-(3/4+5/6)-2/3 =0-1/2-(9/12+12/10)-2/3 =0-1/2-19/12-2/3 =0-(1/2+19/12+2/3) =0-97/36 =-3