帮忙化简下(2x+y)^2-(2x+y)(x-y)-2(x-2y)(x+2y)看了头大``帮忙下`谢谢`_数学解答

帮忙化简下(2x+y)^2-(2x+y)(x-y)-2(x-2y)(x+2y)
看了头大``帮忙下`谢谢`

人气：124 ℃　时间：2020-05-07 23:33:56

解答

(2x+y)^2-(2x+y)(x-y)-2(x-2y)(x+2y)
=4x^2+4xy+y^2-(2x^2-xy-y^2)-2(x^2-4y^2)
=(4x^2-2x^2-2x^2)+(4xy+xy)+(y^2+y^2+8y^2)
=10y^2+5xy
=5y(2y+x)