已知（x+y）=12,（x-y）=6,求2x³y+2x y³∵x+y=12,x-y=6,∴2x=18,x=9,y=3.2x³y+2xy³=2xy(x²+y²)=2xy[(x-y)²+2xy]=54[36+54]=54×90=4860