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            • 1.

              已知数列\(\{a_{n}\}\)的首项\(a_{1}=1\),前\(n\)项的和为\(S_{n}\),且满足\(2a_{n+1}+S_{n}=2(n∈N^{*})\),则满足\(\dfrac{1\mathrm{\ }001}{1\mathrm{\ }000} < \dfrac{S_{2n}}{S_{n}} < \dfrac{11}{10}\)的\(n\)的最大值为              \(.\) 

            • 2. 设等比数列\(\{ \)\(a_{n}\)\(\}\)满足 \(a\)\({\,\!}_{1}\) \(+a\)\({\,\!}_{3}\) \(=\)\(10\), \(a\)\({\,\!}_{2}\) \(+a\)\({\,\!}_{4}\) \(=\)\(5\),则 \(a\)\({\,\!}_{1}\) \(a\)\({\,\!}_{2}…\) \(a_{n}\)的最大值为                              
            • 3.

              数列\(\left\{ {{a}_{n}} \right\}\)是各项为正数的等比数列,且\({{a}_{4}}=2\),已知函数\(f(x)={\log }_{ \frac{1}{2}}x \),则\(f\left( a_{1}^{3} \right)+f\left( a_{2}^{3} \right)+\cdot \cdot \cdot +f\left( a_{7}^{3} \right)=\)(    )

              A.\(−6 \)
              B.\(−21 \)
              C.\(−12 \)
              D.\(21 \)
            • 4.

              已知等比数列\(\{\)\(a_{n}\)\(\}\)满足\(a\)\({\,\!}_{1}=3\),\(a\)\({\,\!}_{1}+\)\(a\)\({\,\!}_{3}+\)\(a\)\({\,\!}_{5}=21\),则\(a\)\({\,\!}_{3}+\)\(a\)\({\,\!}_{5}+\)\(a\)\({\,\!}_{7}=(\)  \()\)

              A.\(21\)         
              B.\(42\)       
              C.\(63\)         
              D.\(84\)
            • 5.\(S_{n}\)为等比数列\(\{ \)\(a_{n}\)\(\}\)的前 \(n\)项和, \(a\)\({\,\!}_{2}-8\) \(a\)\({\,\!}_{5}=0\),则\( \dfrac{S_{8}}{S_{4}}\)的值为(    )
              A.\( \dfrac{1}{2}\)                             
              B.\( \dfrac{17}{16}\)
              C.\(2\)                                       
              D.\(17\)
            • 6.
              若等比数列\(a_{n}\)满足\(a_{n}a_{n+1}=16^{n}\),则公比为\((\)  \()\)
              A.\(2\)
              B.\(4\)
              C.\(8\)
              D.\(16\)
            • 7. 函数\(f(x)=\log _{2} \dfrac {x}{4}\),等比数列\(\{a_{n}\}\)中,\(a_{2}⋅a_{5}⋅a_{8}=8\),则\(f(a_{1})+f(a_{2})+…+f(a_{9})=\) ______ .
            • 8.

              在等比数列\(\{a_{n}\}\)中,\(S_{n}\)表示前\(n\)项和,若\(a_{3}=2S_{2}+1\),\(a_{4}=2S_{3}+1\),则公比\(q\)等于________.

            • 9. 已知\(\{ \)\(a_{n}\)\(\}\)是公差为\(3\)的等差数列,数列\(\{ \)\(b_{n}\)\(\}\)满足 \(b\)\({\,\!}_{1}=1\), \(b\)\({\,\!}_{2}= \dfrac{1}{3}\), \(a_{n}b_{n}\)\({\,\!}_{+1}+\) \(b_{n}\)\({\,\!}_{+1}=\) \(nb_{n}\)

              \((1)\)求\(\{\)\(a_{n}\)\(\}\)的通项公式;

              \((2)\)求\(\{\)\(b_{n}\)\(\}\)的前\(n\)项和.

            • 10.

              已知首项为\(\dfrac{3}{2}\)的等比数列\(\{{{a}_{n}}\}\)的前\(n\)项和为\({{S}_{n}}\),\((n\in {{N}^{*}})\),且\(-2{{S}_{2}},{{S}_{3}},4{{S}_{4}}\)成等差数列,

              \((\)Ⅰ\()\)求数列\(\{{{a}_{n}}\}\)的通项公式;

              \((\)Ⅱ\()\)求\({{S}_{n}}(n\in {{N}^{*}})\)的最值.

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