1.x²y+xy²=xy(x+y)=4x6=24
2.(x/4)²+(2x1x x/4)+1²=(x/4+1)²
3.1.x²y²-y²=y²(x²-1)
2.除以3 a²-2a+1=(a-1)²
3.(x-y)²=(y-x)²
∴原式=(x-y)²(a-b)
4.乘2 x1.x²y+xy²=xy(x+y)=4x6=24
2.(x/4)²+(2x1x x/4)+1²=(x/4+1)²
3.1.x²y²-y²=y²(x²-1)
2.除以3 a²-2a+1=(a-1)²
3.(x-y)²=(y-x)²
∴原式=(x-y)²(a-b)
4.乘2 x²-2xy+y²=(x-y)²