已知(x-3)^2+丨3y+1丨=0.求3x^2y-[2xy-2(xy-3/2)+xy]+3xy^2的值

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已知(x-3)^2+丨3y+1丨=0.求3x^2y-[2xy-2(xy-3/2)+xy]+3xy^2的值

已知(x-3)^2+丨3y+1丨=0.求3x^2y-[2xy-2(xy-3/2)+xy]+3xy^2的值
已知(x-3)^2+丨3y+1丨=0.求3x^2y-[2xy-2(xy-3/2)+xy]+3xy^2的值

已知(x-3)^2+丨3y+1丨=0.求3x^2y-[2xy-2(xy-3/2)+xy]+3xy^2的值
(x-3)^2+丨3y+1丨=0
x-3=0, 3y+1=0
x=3, y=-1/3
3x^2y-[2xy-2(xy-3/2)+xy]+3xy^2
=3x^2y-2xy+2xy-3-xy+3xy^2
=3x^2y-xy+3xy^2-3
=3*9*(-1/3)-3*(-1/3)+3*3*(-1/3)^2-3
=-9+1+1-3
=-10

已知(x-3)^2+丨3y+1丨=0.
x-3=0 x=3
3y+1=0 y=-1/3
3x^2y-[2xy-2(xy-3/2)+xy]+3xy^2
=3x^2y-2xy+2xy-3-xy+3xy^2
=3x^2y-3-xy+3xy^2
=xy(3x-1+3y)
=3×1/3×(3×3-1+3×1/3)
=1×(9-1+1)
=9