由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?

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由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?
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由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?
由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?

由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?
2(x+xy)-[(xy-3y)-x]-(-xy)
=2x+2xy-xy+3y+x+xy
=3x+3y+2xy
=3(x+y)+2xy
=3*(-2)+2*3
=0

2(x+xy)-[(xy-3y)-x]-(-xy)
=2x+2xy-xy+3y+x+xy
=2xy+3(x+y)
∵x+y=-2,xy=3
∴原式=6-6=0

原式=2x+2xy-xy+3y+x+xy
=3x+3y+2xy
=3(x+y)+2xy
=-6+6
=0