題目 Suppose that {ak} is a decreasing sequence of real numbers.
∞
Prove that if Σak converges, then kak→0 as k→∞.
k=1
我目前會的
∞
since Σak converges,so ak→0 as k→∞
k=1
by {ak} is decreasing and →0 ,so {ak} is nonegative sequence
再來好像要分2k跟2k+1討論, 可是我不太清楚要怎麼做
可以教我嗎 謝謝
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※ 編輯: eric80520 來自: 112.105.127.195 (04/09 23:19)