分解因式(xy+1)(x+y+xy+1)+xy

分类: 作业答案 • 2022-05-31 22:01:28

问题描述：

答

(xy+1)(x+y+xy+1)+xy
=(xy+1)[(x+y)+(xy+1)]+xy
=(xy+1)²＋(xy+1)(x+y)+xy
=(xy+1＋x)(xy+1＋y)(十字相乘)
xy+1 x
×
xy+1 y