(2x^2+ax-y+6)-(2bx^2-3x+5y-1)的值与字母x所取得值无关说明x的系数为0(2x^2+ax-y+6)-(2bx^2-3x+5y-1）=(2-2b)x^2+(a+3)x-(1+5)y+7所以x的系数为02-2b=0,a+3=0=>a=-3,b=11/3*a^3-2b^2-(1/4*a3-3b)=1/3*a^3-2b^2-1/4*...