問題是要express the following in Σ notation
11+12+13+...+20
9
Σ(11+i)
i=0
跟
20
Σi
i=11
2個都可以做答案嗎?
請略略解釋一下~
[maths]f4 summation question
2009-10-17 6:46 pm
回答 (2)
2009-10-17 7:01 pm
✔ 最佳答案
Σ[i = 0 to 9] (i + 11)^2
可以改他的index代表字母為k, 結果明顯是一樣的
Σ[k = 0 to 9] (k + 11)^2
現代 i = k + 11
k = 0 => i = 11
k = 9 => i = 20
因此Σ[k = 0 to 9] (k + 11)^2 = Σ[i = 11 to 20] i^2
Σ[i = 0 to 9] (i + 11)^2 = Σ[i = 11 to 20] i^2
2009-10-21 3:07 am
收錄日期: 2021-04-13 16:53:39
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20091017000051KK00396