设无穷等比数列{an}的前n项和为Sn,首项是a1,若limSn=a1^2,a1∈(1,4)则公比q的取值范围是?

设无穷等比数列{an}的前n项和为Sn,首项是a1,若limSn=a1^2,a1∈(1,4)则公比q的取值范围是?
设无穷等比数列{an}的前n项和为Sn,首项是a1,若limSn=a1^2,a1∈(1,4)
则公比q的取值范围是?

设无穷等比数列{an}的前n项和为Sn,首项是a1,若limSn=a1^2,a1∈(1,4)则公比q的取值范围是?
limSn=a1/(1-q)=a1^2 ①
|q|-q>-3/4
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