设数列{an}是公比为q的等比数列,|q|>1,令bn=an+2(n∈N*),若数列{bn}有连续四项在集合{-52,-22,20,38,83}中,则公比q的值为________.
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解析分析:由数列{bn}有连续四项在集合{-52,-22,20,38,83}中和bn=an+2,确定数列{an}的连续四项,即可求得公比
解答:∵bn=an+2∴an=bn-2∵数列{bn}有连续四项在集合{-52,-22,20,38,83}中∴数列{an}有连续四项在集合{-54,-24,18,36,81}中又∵数列{an}是公比为q的等比数列,|q|>1∴在集合{-54,-24,18,36,81}中,数列{an}的连续四项只能是:-24,36,-54,81∴故