括号三的n加二次方减三乘三的n次方括号除以三的n减一次方等于多少?

2025-06-20 08:18:11
推荐回答(1个)
回答1:

(3ⁿ﹢²-3x3ⁿ)÷3ⁿ-¹
=(3ⁿ﹢²-3ⁿ﹢¹)÷3ⁿ-¹
=18