已知x-y-2的绝对值+(2xy-1)的平方=0,求x(x+y)(x-y)-x(y-x)的平方的值.
问题描述:
已知x-y-2的绝对值+(2xy-1)的平方=0,求x(x+y)(x-y)-x(y-x)的平方的值.
答
易知x-y-2=0,2xy-1=0
x-y=2,2xy=1
原式=x(x+y)(x-y)-x(x-y)²
=x(x-y)(x+y-x+y)
=2xy(x-y)
=1×2=2