(a+b)^3=a^3+3a^2b+3ab^2+b^3 (a-b)^3=?(a+b)^3=a^3+3a^2b+3ab^2+b^3 ,那么(a-b)^3=?

来源：学生作业学帮网编辑：学帮网时间：2024/06/16 06:21:39

(a+b)^3=a^3+3a^2b+3ab^2+b^3 (a-b)^3=?
(a+b)^3=a^3+3a^2b+3ab^2+b^3 ,那么(a-b)^3=?

(a-b)^3=（a+(-b))^3=a^3+3a^2(-b)+3a(-b)^2+(-b)^3
=a^3-3a^2b+3ab^2-b^3