※ 引述《CBH (吸逼A去)》之銘言：
: https://i.imgur.com/ZNNyJqc.jpg
: 第8 求解~
總之 a, b, c > 1
那麼對 x_n 的其中一個加項 (以 a,α 為例好了)
αa^n α α
有 lim ------- = lim --------- = ---- = α (這由 a>1 得)
n->∞ 1 + a^n n->∞ 1/a^n + 1 1
其他加項同理, 所以所求極限 = α+β+γ #
====
之所以要判斷 a,b,c > 1
是因為若 0<a<1 則這個加項的極限為 0/(1+0) = 0 就不是α了
--
'You've sort of made up for it tonight,' said Harry. 'Getting the
sword. Finishing the Horcrux. Saving my life.'
'That makes me sound a lot cooler then I was,' Ron mumbled.
'Stuff like that always sounds cooler then it really was,' said
Harry. 'I've been trying to tell you that for years.'
-- Harry Potter and the Deathly Hollows, P.308
--
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※ 編輯: LPH66 (123.195.192.32), 03/24/2019 00:21:04