[(x+y)²-(x-y)]²÷2xy

[(x+y)²-(x-y)]²÷2xy
[(x+y)²-(x-y)]²÷2xy

[(x+y)²-(x-y)]²÷2xy
[(x+y)²-(x-y)]²÷2xy
=(x+y+x-y)(x+y-x+y)÷2xy
=4xy÷2xy
=2
如追加其它问题,

[(x+y)²-(x-y)²]÷2xy
=[(x²+2xy+y²)-(x²-2xy+y²)]÷2xy
=4xy/2xy
=2

如果不懂，请追问，祝学习愉快！