用乘法公式计算：(3a-2b)(9a^2+6ab+4b^2) (a-1)(a+1)(a^4+a^2+1)1）(3a-2b)(9a^_数学解答

用乘法公式计算：(3a-2b)(9a^2+6ab+4b^2) (a-1)(a+1)(a^4+a^2+1)
1）(3a-2b)(9a^2+6ab+4b^2)
2）(a-1)(a+1)(a^4+a^2+1)

人气：334 ℃　时间：2019-10-11 19:57:00

解答

(3a-2b)(9a^2+6ab+4b^2)
=(3a)³-(2b)³
=27a³-8b³
(a-1)(a+1)(a^4+a^2+1)
=(a²-1)(a^4+a^2+1)
=a^6-1