分解因式9(x+y)三次方-6(x+y)两次方+(x+y) 快

问题描述:

分解因式9(x+y)三次方-6(x+y)两次方+(x+y) 快

(x+y)[9(x+y)^2-6(x+y)+1]=(x+y){[3(x+y)]^2-6(x+y)+1}=(x+y)[3(x+y)-1)]^2