令 x=（a-b）开三次方,y=（b-c）开三次方,则x+y=2,a-c=（a-b)+(b-c)=x^3+y^3=26,即x^3+y^3=（x+y)^3-3xy(x+y)=8-6xy=26,得xy=-3,联立x+y=2,解之得x=3,y=-1,或x=-1,y=3a-2b+c=(a-b)-(b-c)=x^3-y^3当x=-1,y=3,a-2b+c=x...