分解因式:1+2xy-x^2-y^2 x^3-x^2-9x+9 15x^2y-30xy^2+3x-6y

分类: 作业答案 • 2023-01-22 07:41:08

问题描述：

答

1+2xy-x²-y²＝1-(x²-2xy+y²)=1-(x-y)²=(1+x-y)(1-x+y)x³-x²-9x+9=x²(x-1)-9(x-1)=(x²-9)(x-1)=(x+3)(x-3)(x-1)15x²y-30xy²+3x-6y=15xy(x-2y)+3(x-2y)=(15xy...