|x+3|+(y-1/3)的平方=0
|x+3|=0,(y-1/3)的平方=0
x=-3
y=1/3
3x²y-[2xy²-2(xy-2/3x²y)-xy]+3xy²
=3x²y-[2xy²-2xy+4/3x²y-xy]+3xy²
=3x²y-[2xy²-2xy-xy+4/3x²y]+3xy²
=3x²y-[2xy²-3xy+4/3x²y]+3xy²
=3x²y-2xy²+3xy-4/3x²y+3xy²
=3x²y-4/3x²y+3xy²-2xy²+3xy
=5/3x²y+xy²+3xy
=xy(5/3x+y+3)
=-3*1/3*[5/3*(-3)+1/3+3]
=-(-5+4/3)
=-(-11/3)
=11/3