(a-b)³等于什么

问题描述:

(a-b)³等于什么

楼主您好:
(a-b)³
=a³-3a²b+3ab²-b³
祝楼主学习进步

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

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