解(2x+y)的平方-(x+2y)的平方
=(2x+y)²-(x+2y)²
=[(2x+y)+(x+2y)][(2x+y)-(x+2y)]
=[(3x+3y)][(x-y)]
=3(x+y)(x-y)
根据平方差公式 =(2x+y-x-2y)*(2x+y+x+2y)=(x-y)*(3x+3y)=3(x平方+y平方)
平方差公式!!答案:(2x+y+x+2y)(2x+y-x-2y)自己化简一下
根据平方差公式
(2x+y)²-(x+2y)²
=[(2x+y)+(x+2y)][(2x+y)-(x+2y)]
=[(3x+3y)][(x-y)]
=3(x+y)(x-y)
(2X+y)^2 -(X+2y)^2 =4X^2+4Xy+y^2-X^2-4Xy-4y^2 =3X^2-3y^2 =(√3X+√3y)(√3X-√3 y)