已知分式1/x-1/2y=1/3,则2x+3xy-4y/x-3xy-2y=
问题描述:
已知分式1/x-1/2y=1/3,则2x+3xy-4y/x-3xy-2y=
答
1/X-1/2Y=1/3 6y-3x=2xy 2y-x=2/3xy x-2y=-2/3xy 所以(2X+3XY-4Y)/(X-3XY-2Y) =[2(x-2y)+3xy]/[(x-2y)-3xy] =[2*(-2/3xy)+3xy]/(-2/3xy-3xy) =(5/3xy)/(-11/3xy) =-5/11