Question

试探究：当a、b为何值时,代数式（2x^2+ax-y+b）-(2bx^2-3x+5y-1)的值与字母x的取值无关.

Answer 1

（2x^2+ax-y+b）-(2bx^2-3x+5y-1)的值与字母x的取值无关

与x取值无关,说明x的系数为0

化简

（2x^2+ax-y+b）-(2bx^2-3x+5y-1)

=(2-2b)x^2+(a+3)x-6y+b+1

=>2-2b=0 ,a+3=0

=> a=-3,b=1