分式加减2x²/（x-y）²+x²-4xy/（y-x）²-x²-2y²/x²-2xy+y²

分类: 作业答案 • 2022-07-12 08:52:03

问题描述：

答

原式=2x²/(x-y)²+(x²-4xy)/(x-y)²-(x²-2y²)/(x-y)²=(2x²+x²-4xy-x²+2y²)/(x-y)²=(2x²-4xy+2y²)/(x-y)²=2(x-y)²/(x-y)²=2