(x-y)²-2y(x+y)怎么化简
问题描述:
(x-y)²-2y(x+y)怎么化简
答
(x-y)²-2y(x+y)=x²-2xy+y²-2xy-2y²=x²-4xy-y²=x²-4xy+4y²-5y²=(x-2y)²-5y²=(x-2y+根5)*(x-2y-根5)
(x-y)²-2y(x+y)怎么化简
(x-y)²-2y(x+y)=x²-2xy+y²-2xy-2y²=x²-4xy-y²=x²-4xy+4y²-5y²=(x-2y)²-5y²=(x-2y+根5)*(x-2y-根5)