1.解两个方程构成的方程组,有:
x=2,y=3
或
x=3,y=2
所以有:
(1)x³y+2x²y²+xy³=24+72+54=150
(2)x³y+2x²y²+xy³=54+72+24=150
也就是,结果为150.
解法二:x³y+2x²y²+xy³=xy(x+y)^2={[(x+y)^2-(x²+y²)]/2}(x+y)^2={[5^2-13]/2}*5^2=150
2.x²+2x+y²-6y+10=(x+1)^2+(y-3)^2=0
故,x=-1,y=3
有,x^y=-1
3.x(x-1)-(x²-y)+2=y-x+2=0
这说明:x-y=2
x²+y²/2-xy=(x-y)^2/2=2