求﹙x²+y²﹚²-4x²y²的值

问题描述:

求﹙x²+y²﹚²-4x²y²的值

=﹙x²+y²﹚²-(2xy)²
=(x²+y²+2xy)(x²+y²-2xy)
=(x+y)²(x-y)²

﹙x²+y²﹚²-4x²y²
=﹙x²+y²﹚²-(2xy)²
=(x²+y²+2xy)(x²+y²-2xy)
=(x+y)²(x-y)²

﹙x²+y²﹚²-4x²y²=x^4+2x²y²+y^4-4x²y²=x^4-2x²y²+y^4=﹙x²-y²﹚²=(x+y)²(x-y)² 不懂可追问,有帮助请采纳,谢谢!...

﹙x²+y²﹚²-4x²y²
=(x^2+y^2-2xy)(x^2+y^2+2xy)
=(x-y)^2(x+y)^2