化简(2x+y)(2x-y)-(x+2y)(x-2y-1)
问题描述:
化简(2x+y)(2x-y)-(x+2y)(x-2y-1)
答
(2x+y)(2x-y)-(x+2y)(x-2y-1)
= 4x²-y²-(x+2y)(x-2y)+(x+2y)
=4x²-y²-x²+4y²+x+2y
=3x²+3y²+x+2y