Question

数学题高手来

【（xy+2)(xy-2)-2x的平方y的平方+4】除（xy)
写出过程

Answer 1

原式=(xy*xy-4-4xy*xy+4)/(xy)=-3xy

Answer 2

[(xy+2)(xy-2)-2(x^2)(y^2)+4]/xy=[(x^2)(y^2)-4-2(x^2)(y^2)+4]/xy=-(x^2)(y^2)/xy=-xy

Answer 3

=(x^2y^2-4-2x^2y^2+4)/(xy)
=(-x^2y^2)/(xy)
=-xy