若x-y=5,xy=6 则x²y-xy²=—————,2x²+2y²________

若x-y=5,xy=6 则x²y-xy²=—————,2x²+2y²________
若x-y=5,xy=6 则x²y-xy²=—————,2x²+2y²________

若x-y=5,xy=6 则x²y-xy²=—————,2x²+2y²________
若x-y=5,xy=6
则
x²y-xy²
=xy(x-y)
=6×5
=30;
2x²+2y²
=2(x²+y²)
=2[(x-y)²+2xy]
=2×(5²+2×6)
=2×(25+12)
=2×37
=74

30 和 74

x²y-xy²=xy（x-y）=6*5=30
2x²+2y²=2x²+2y²-4xy+4xy=2（x-y）^2 +4xy=2*5^2 + 4*6=50 +24=74

x²y-xy²=xy(x-y)
2x²+2y²=2(x²+y²)
=2[(x-y)²+2xy]
这样代入就行了
答案是30，74