已知m^2=n+2,n^2=m+2(m不等于n),先化简再求m^3-2mn+n^3的值

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已知m^2=n+2,n^2=m+2(m不等于n),先化简再求m^3-2mn+n^3的值已知m^2=n+2,n^2=m+2(m不等于n),先化简再求m^3-2mn+n^3的值已知m^2=n+2,n^2=

已知m^2=n+2,n^2=m+2(m不等于n),先化简再求m^3-2mn+n^3的值
已知m^2=n+2,n^2=m+2(m不等于n),先化简再求m^3-2mn+n^3的值

已知m^2=n+2,n^2=m+2(m不等于n),先化简再求m^3-2mn+n^3的值
m^2=n+2,n^2=m+2(m≠n),
两式相减,得:m+n=-1
m^3-2mn+n^3
=m*(n+2)-2mn+n*(m+2)
=mn+2m-2mn+mn+2n
=2m+2n
=-2