已知2x-y=4,求4x2-4xy+y2-2x+y-6的值.
问题描述:
已知2x-y=4,求4x2-4xy+y2-2x+y-6的值.
答
∵2x-y=4,
∴4x2-4xy+y2-2x+y-6
=(4x2-4xy+y2)-(2x-y)-6
=(2x-y)2-(2x-y)-6
=16-4-6
=6.