题目内容
计算(2x-3y+1)(2x+3y-1)的结果是( )
A.4x2-12xy+9y2-1 | B.4x2-9y2-6y-1 |
C.4x2+9y2-1 | D.4x2-9y2+6y-1 |
(2x-3y+1)(2x+3y-1),
=[2x-(3y-1)][2x+(3y-1],
=(2x)2-(3y-1)2,
=4x2-9y2+6y-1.
故选D.
=[2x-(3y-1)][2x+(3y-1],
=(2x)2-(3y-1)2,
=4x2-9y2+6y-1.
故选D.
练习册系列答案
相关题目