MT【102】一个常见的因式分解公式

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解答:

$x^3+y^3+1-3xy=(x+y+1)(x^2+y^2+1+xy-x-y)=$

$(x+y+1)(x^2+y^2+1+xy-x-y)=$

$frac{1}{2}(x+y+1)[(x-y)^2+(x-1)^2+(y-1)^2] herefore x=y=1$

原文地址:https://www.cnblogs.com/mathstudy/p/7677151.html