a与b差的立方等于什么
(a-b)³=a³-3a²b+3ab²+b³
(a-b)³=a³-3a²b+3ab²+b³的推导过程如下:
(a-b)³
=(a-b)(a-b)²(分解成两个因式相乘)
=(a-b)(a²-2ab+b²)(把(a-b)²用乘法表达出来)
=a³-3a²b+3ab²-b³(依次相乘得到最后结果)
(a-b)³=a³-3a²b+3ab²+b³
(a-b)³=a³-3a²b+3ab²+b³的推导过程如下:
(a-b)³
=(a-b)(a-b)²(分解成两个因式相乘)
=(a-b)(a²-2ab+b²)(把(a-b)²用乘法表达出来)
=a³-3a²b+3ab²-b³(依次相乘得到最后结果)