解a,b互为相反数则a+b=0c,d互为倒数则cd=1x=3(a-1)-(a-2b)=3a-3-a+2b=2(a+b)-3=-3y=c²d+d²-(d/c+c-1)————cd=1则c=1/d,=c+d²-(d²+c-1)=c-c+1=1∴(2x+y)/3-(3x-2y)/6——是这个吧?=(-6+1)/3-(...