1,若x+y+3=0,求3分之2-2x-2y+(-x-y)的平方 2,已知xy分之x+y=3,求-x+2xy-y分之2x-3xy+2y的值

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1,若x+y+3=0,求3分之2-2x-2y+(-x-y)的平方 2,已知xy分之x+y=3,求-x+2xy-y分之2x-3xy+2y的值

1,若x+y+3=0,求3分之2-2x-2y+(-x-y)的平方 2,已知xy分之x+y=3,求-x+2xy-y分之2x-3xy+2y的值
1,若x+y+3=0,求3分之2-2x-2y+(-x-y)的平方 2,已知xy分之x+y=3,求-x+2xy-y分之2x-3xy+2y的值

1,若x+y+3=0,求3分之2-2x-2y+(-x-y)的平方 2,已知xy分之x+y=3,求-x+2xy-y分之2x-3xy+2y的值
x+y+3=0,x+y=-3
3分之2-2x-2y+(-x-y)的平方
=【2-2(x+y)+(x+y)^2】/3
=(2-6+9)/3
=5/3
(x+y)/xy=3,x+y=3xy
(2x-3xy+2y)/(-x+2xy-y)
=[2(x+y)-3xy]/[2xy-(x+y)]
=3xy/(-xy)
=-3

x+y+3=0
x+y=-3
2/3-2x-2y+(-x-y)^2
=2/3-2(x+y)+(x+y)^2
=2/3-2*(-3)+(-3)^2
=2/3+6+9
=15+2/3
=47/3

-3,我们数学老师说的