已知1除以X的商减去1除以y的商的差为2,则:y-x=2xy
即:(3x-5xy-3y)/(-x+3xy+y)
=[3x-5(y-x)/2-3y]/[-x+3(y-x)/2+y]
=[3x+2.5x-2.5y-3y]/[-x-1.5x+1.5y+y]
=[5.5x-5.5y]/[-2.5x+2.5y]
=5.5(x-y)/-2.5(x-y)
=-55/25
=-11/5
已知1除以X的商减去1除以y的商的差为2,则:y-x=2xy
即:(3x-5xy-3y)/(-x+3xy+y)
=[3x-5(y-x)/2-3y]/[-x+3(y-x)/2+y]
=[3x+2.5x-2.5y-3y]/[-x-1.5x+1.5y+y]
=[5.5x-5.5y]/[-2.5x+2.5y]
=5.5(x-y)/-2.5(x-y)
=-55/25
=-11/5