((xy+2)(xy-2)-2x^2y^2+4)除以2xy,其中x=10,y=-1/5

问题描述:

((xy+2)(xy-2)-2x^2y^2+4)除以2xy,其中x=10,y=-1/5


((xy+2)(xy-2)-2x^2y^2+4)除以2xy
=(x²y²-4-2x²y²+4)/(2xy)
=(-x²y²)/(2xy)
=-xy/2
=-[10*(-1/5)]/2
=2/2
=1