作者justalone101 (ㄚ挺)
看板Math
标题[微积] absolute convergence 一问
时间Tue Mar 29 20:15:26 2011
为什麽
(-1)^k
Σ─────── does not converges absolutely
[k(k+1)]^1/2
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※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 114.40.77.77
※ 编辑: justalone101 来自: 114.40.77.77 (03/29 20:16)
1F:推 air11 :Σ1/[k(k+1)]^1/2 发散 03/29 20:40
2F:→ yueayase :可以考虑用comparison test,并考虑Σ1/k 03/29 23:21
3F:→ yueayase :因为[k(k+1)]^1/2的最高次项看起来不就和1/k相同 03/29 23:22