xy=3-2=1x+y=2√3平方x²+y²+2xy=12x²+y²=12-2xy=10所以原式=xy(x²+y²)=1×10=10
x=√3+√2,y=√3-√2 可得：x+y=√3+√2+√3-√2=2√3xy=(√3+√2)(√3-√2)=3-2=1x³y+xy³ =xy(x²+y²)=xy[(x+y)²-2xy]=(2√3)²-2=10
