已知x-y=2,xy=1,求x的方乘以(x-y)-y的方乘以(y-)的值

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已知x-y=2,xy=1,求x的方乘以(x-y)-y的方乘以(y-)的值

已知x-y=2,xy=1,求x的方乘以(x-y)-y的方乘以(y-)的值
已知x-y=2,xy=1,求x的方乘以(x-y)-y的方乘以(y-)的值

已知x-y=2,xy=1,求x的方乘以(x-y)-y的方乘以(y-)的值
题目没有写完吧?我估计是
x^2*(x-y)-y^2*(y-x)
=(x^2+y^2 )*(x-y)
=(x^2+y^2-2xy +2xy)*(x-y)
=[(x-y)^2+2xy ]*(x-y)
=(2^2+2*1)*2
= 6*2
=12