(a b c)3怎么算

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(a b c)3怎么算
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(a b c)3怎么算
(a b c)3怎么算

(a b c)3怎么算
(a+ b+ c)^3=(a+b+c)(a+b+c)^2
=(a+b+c)(a^2+2ab+b^2+2bc+c^2+2ac)
=(a^3+2a^2b+ab^2+2abc+ac^2+2a^2c)+(a^2b+2ab^2+b^3+2b^2c+bc^2+2abc)
+(a^2c+2abc+b^2c+2bc^2+c^3+2ac^2)
=a^3+b^3+c^3+3a^2b+3ab^2+3a^2c+3ac^2+3b^2c+3bc^2+6abc