通分:(1)1/(2-x)²,x/(x+2)(x-2)(2)1/x²-1,2x/x²-3x

1个回答

  • 1﹚

    1/﹙2-x﹚²=1/﹙x-2﹚²=﹙x+2﹚/[﹙x-2﹚²﹙x+2﹚]

    1/[﹙x+2﹚﹙x-2﹚]=﹙x-2﹚/[﹙x-2﹚²﹙x+2﹚]

    2﹚

    1/﹙x²-1﹚=1/[﹙x+1﹚﹙x-1﹚]=﹙x-2﹚/[﹙x+1﹚﹙x-1﹚﹙x-2﹚]

    2x/﹙x²-3x+2﹚=2x/[﹙x-1﹚﹙x-2﹚]=2x﹙x+1﹚/[﹙x+1﹚﹙x-1﹚﹙x-2﹚]