1. Find the sum of the series (2+log2) + (4+log4) + (8+log8) + ‧‧‧to
10 terms.
(Ans: 2046 + 55 log2)
這條是否可以利用 2^n + log2^n 來計, 是否要抽 common factor
thx
F.6 math...AS/ GS ...急....thx
2013-10-27 3:02 am
回答 (1)
2013-10-27 3:17 am
✔ 最佳答案
(2+log2) + (4+log4) + (8+log8) + ‧‧‧to 10 terms.= 2+4+8+16+32+.......1024 + log2 + log4 + log8 + ...... log1024
= 2+4+8+16+32+.......1024 + log2 + 2log2 + 3log2 + ...... 10log2
= 2+4+8+16+32+.......1024 + log2(1+2+3+......+10)
= (2)(1-2^10)/(1-2) + 55log2
= 2046 + 55log2
收錄日期: 2021-04-13 19:46:30
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20131026000051KK00159