星辰奇缘65级宠物选择:(x-y)^2-4(x^2-y^2)+4(x+y)^2
来源:百度文库 编辑:高校问答 时间:2024/05/28 19:24:52
分解因式,谢谢
(x-y)^2-4(x^2-y^2)+4(x+y)^2
=x^2-2xy+y^2-4x^2+4y^2+4x^2+8xy+4y^2
=x^2+6xy+9y^2
=(x+3y)^2
(x-y)^2-4(x^2-y^2)+4(x+y)^2
=x^2-2xy+y^2-4x^2+4y^2+4x^2+8xy+4y^2
=x^2+6xy+9y^2
=(x+3y)^2