• 等差数列{an}、{bn}的前n项和分别为Sn、Tn,若SnTn=3n-12n+3,则a6b6= .试题及答案-填空题-云返教育

    • 试题详情

      等差数列{an}、{bn}的前n项和分别为Sn、Tn,若
      Sn
      Tn
      =
      3n-1
      2n+3
      ,则
      a6
      b6
      =         

      试题解答


      32
      25

      解:∵数列{an}、{bn}是等差数列,
      S11=
      (a1+a11)?11
      2
      =11a6
      T11=
      (b1+b11)?11
      2
      =11b6
      a6
      b6
      =
      S11
      T11
      =
      3×11-1
      2×11+3
      =
      32
      25

      故答案为:
      32
      25
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