※ 引述《iddee ()》之銘言:
: 求 lim(x->oo) √[x + √(x + √x)] - √x
: ANS: 1/2
lim √x {√[1 + √[1/x + 1/x^(3/2)] ] - 1}
x→∞
√x √[1/x + 1/x^(3/2)]
= lim -----------------------------------
x→∞ √[1 + √[1/x + 1/x^(3/2)] ] + 1
√[1 + 1/x^(1/2)]
= lim ----------------------------------
x→∞ √[1 + √[1/x + 1/x^(3/2)] ] + 1
1
= -----------
2
--
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