二、因式分解 1.(x2+1)2-4x² 2.(x-y)2-2(x-y)-8

问题描述:

二、因式分解 1.(x2+1)2-4x² 2.(x-y)2-2(x-y)-8

  1. (x2+1)2-4x²

    2x^2+2-4x^2=2-2x^2=2(1+x)(1-x)

    2.(x-y)2-2(x-y)-8

    (x-y+2)(x-y-4)

     

1.(x2+1)2-4x²
=(x²+1+2x)(x²+1-2x)
=(x+1)²(x-1)²
2.(x-y)2-2(x-y)-8
=(x-y+2)(x-y-4)