已知代数式(4x2+ax-y+6) -(2BX2-2X+5Y-1)的值与字母x的取值无关,求代数式3(a2-2ab-b2) -(4a2+a

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已知代数式(4x2+ax-y+6) -(2BX2-2X+5Y-1)的值与字母x的取值无关,求代数式3(a2-2ab-b2) -(4a2+a

4x2+ax-y+6) -(2BX2-2X+5Y-1)的值与字母x的取值无关 4x2+ax-y+6) -(2BX2-2X+5Y-1) =4x2+ax-y+6 -2BX2+2X-5Y+1 =(4-2B)X^2+(a+2)x-6y+7 所以x的系数应该为04-2b=0 a+2=0 =》 b=2,a=-2 3(a2-2ab-b...