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因式分解(3m-2n)^3+(3m+2n)^3

题目详情
因式分解(3m-2n)^3+(3m+2n)^3
▼优质解答
答案和解析
(3m-2n)^3+(3m+2n)^3
=(3m-2n+3m+2n)[(3m-2n)^2-(3m-2n)(3m+2n)+(3m+2n)^2]
=6m[9m^2-12mn+4n^2-9m^2+4n^2+9m^2+12mn+4n^2]
=6m(9m^2+12n^2)
=18m(3m^2+4n^2)