来源：学生作业帮 编辑：灵鹊做题网作业帮 分类：数学作业 时间：2024/05/15 16:48:38
数列性质
a(n+1)-an=2n
an-a(n-1) = 2(n-1)
an -a1 = 2+4+6+...+2(n-1)
= n(n-1)
an =n(n-1) +33
an/n = n-1 + 33/n
let
f(x) = x-1 +33/x
f'(x) = 1 -33/x^2=0
x^2-33=0
x=5.74
a5/5 = 5-1+33/5 = 53/5
a6/6 = 6-1 +33/6 = 63/6 = 21/2
min an/n = a6/6 = 21/2
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