[1] 9(a-b)^2+12(a-b)+a [2] 4(x-2)-(x+2)(x-2)

问题描述:

[1] 9(a-b)^2+12(a-b)+a [2] 4(x-2)-(x+2)(x-2)

是分解因式,还是整式乘法[1] 9(a-b)²+12(a-b)+a =9²-18ab+b²+12a-12b+a=9²-18ab+b²+13a-12b[2] 4(x-2)-(x+2)(x-2)=4x-8-x²+4=-x²+4x-4=-(x²-4x+4)=-(x-2)²分解因式[1]9(a-b)²+12(a-b)+a=9a²-18ab+b²+12a-12b+a=9a²-18ab+b²+13a-12b[1]题有误,请判定。[2]4(x-2)-(x+2)(x-2)=4x-8-x²+4=-x²+4x-4=-(x²-4x+4)=-(x-2)²