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            • 1.
              已知\(\{a_{n}\}\)是等比数列,\(a_{5}= \dfrac {1}{2},4a_{3}+a_{7}=2\),则\(a_{7}=\) ______ .
            • 2.
              已知等差数列\(\{a_{n}\}\)的公差为\(2\),若\(a_{1}\),\(a_{3}\),\(a_{4}\)成等比数列,则\(a_{3}=(\)  \()\)
              A.\(-10\)
              B.\(-6\)
              C.\(-8\)
              D.\(-4\)
            • 3.
              设\(\{a_{n}\}\)是公比为\(q\)的等比数列,\(|q| > 1\),令\(b_{n}=a_{n}+1(n=1,2,…)\),若数列\(\{b_{n}\}\)有连续四项在集合\(\{-53,-23,19,37,82\}\)中,则\(q\)等于\((\)  \()\)
              A.\(- \dfrac {1}{2}\)
              B.\( \dfrac {1}{2}\)
              C.\(- \dfrac {3}{2}\)
              D.\( \dfrac {3}{2}\)
            • 4.
              已知等比数列\(\{a_{n}\}\)的首项为\(1\),公比\(q\neq -1\),且\(a_{5}+a_{4}=3(a_{3}+a_{2})\),则\(a_{5}=(\)  \()\)
              A.\(-9\)
              B.\(9\)
              C.\(-81\)
              D.\(81\)
            • 5.
              正项等比数列\(\{a_{n}\}\)中,\(S_{n}\)为\(\{a_{n}\}\)的前\(n\)项和,若\(S_{3}+a_{2}=9a_{3}\),则其公比为\((\)  \()\)
              A.\( \dfrac {1}{2}\)
              B.\( \dfrac {1}{3}\)
              C.\( \dfrac {1}{4}\)
              D.\( \dfrac {1}{8}\)
            • 6.
              已知等比数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(a_{1}=2\),\(a_{n}=-64\),\(S_{n}=-42\),则公比\(q\)等于\((\)  \()\)
              A.\(- \dfrac {1}{2}\)
              B.\(-3\)
              C.\(-2\)
              D.\(4\)
            • 7.
              在各项均为正数的等比数列\(\{a_{n}\}\)中,\(a_{6}=3\),则\(a_{4}+a_{8}=(\)  \()\)
              A.有最小值\(6\)
              B.有最大值\(6\)
              C.有最大值\(9\)
              D.有最小值\(3\)
            • 8. 已知等比数列{an}中,a1+a3=,则a6= ______
            • 9. 等比数列{an}满足:a1=a(a>0),成等比数列,若{an}唯一,则a的值等于 ______
            • 10. 在等比数列{an}中,若a2a5=-,a2+a3+a4+a5=,则=(  )
              A.1
              B.
              C.
              D.
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