a的三次方-3a的平方+3a-1
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/24 07:53:15
![a的三次方-3a的平方+3a-1](/uploads/image/z/1728637-61-7.jpg?t=a%E7%9A%84%E4%B8%89%E6%AC%A1%E6%96%B9-3a%E7%9A%84%E5%B9%B3%E6%96%B9%2B3a-1)
a的三次方-3a的平方+3a-1
a的三次方-3a的平方+3a-1
a的三次方-3a的平方+3a-1
a ³ -3a²+3a-1
=(a ³ -1)-(3a²-3a)
=(a-1)(a ²+a+1)-3a(a-1)
=(a-1)(a ²+a+1-3a)
=(a-1)(a -1)²
=(a-1) ³
原式=(a^3-1)-(3a^2-3a)
=(a-1)(a^2+a+1)-3a(a-1)
=(a-1)(a^2-2a+1)
=(a-1)^3
是3*a方还是[3a]方啊