在数列{an}中,已知a1=2/9,且an=SnSn-1(n>=2),求lim an/(Sn^2)
人气:375 ℃ 时间:2020-02-03 13:41:12
解答
lim an/(Sn^2)=lim(Sn^2-1)/(Sn^2)=1-lim 1/(Sn^2)
lim(Sn^2)=无穷,所以最后=1
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