问题 解答题

已知2x-y=4,求4x2-4xy+y2-2x+y-6的值.

答案

∵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.

单项选择题
填空题