待定系数法因式分解：（1）x方+2xy+y方+x+y-2 （2）x方+xy-2y方+2x+7y-3

分类: 作业答案 • 2021-11-12 23:56:14

问题描述：

答

（1）x方+2xy+y方+x+y-2
=(x+y)²+(x+y)-2
=(x+y+2)(x+y-1)
（2）x方+xy-2y方+2x+7y-3
=(x+2y)(x-y)+2x+7y-3
=(x+2y-1)(x-y+3)