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            • 1. 已知数列\(\{{{a}_{n}}\}\)的前\(n\)项和为\({{S}_{n}}\),若\(3{{S}_{n}}=2{{a}_{n}}-3n\),则\({{a}_{2018}}=\)

              A.\({{2}^{2018}}-1\)
              B.\({{3}^{2018}}-6\)
              C.\({{\left( \dfrac{1}{2} \right)}^{2018}}-\dfrac{7}{2}\)
              D.\({{\left( \dfrac{1}{3} \right)}^{2018}}-\dfrac{10}{3}\) 
            • 2.

              已知数列\(\{a_{n}\}\)是以\(a\)为首项,\(b\)为公比的等比数列,数列\(\{b_{n}\}\)满足\(b_{n}=1+a_{1}+a_{2}+…+a_{n}(n=1,2,…)\),数列\(\{c_{n}\}\)满足\(c_{n}=2+b_{1}+b_{2}+…+b_{n}(n=1,2,…)\),若\(\{c_{n}\}\)为等比数列,则\(a+b=\)

              A.\(\sqrt{2}\)
              B.\(3\)
              C.\(\sqrt{5}\)
              D.\(6\)
            • 3.
              等比数列\(\{a_{n}\}\)中,\(a_{5}=4\),则\(a_{2}⋅a_{8}=(\)  \()\)
              A.\(4\)
              B.\(8\)
              C.\(16\)
              D.\(32\)
            • 4.
              已知等比数列\(\{a_{n}\}\)的通项公式为\(a_{n}=3^{n+2}(n∈N^{*})\),则该数列的公比是\((\)  \()\)
              A.\( \dfrac {1}{9}\)
              B.\(9\)
              C.\( \dfrac {1}{3}\)
              D.\(3\)
            • 5.

              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\(3\)
            • 6.

              一直角三角形三边长成等比数列,则(    )

              A.三边长之比为\(3\):\(4\):\(5\)            
              B.三边长之比为\(3\):\(\sqrt{3} \):\(1\)
              C.较大锐角的正弦为\(\dfrac{ \sqrt{5}-1}{2} \)
              D.较小锐角的正弦为\(\dfrac{ \sqrt{5}-1}{2} \)
            • 7. 在正项等比数列\(\{an\}\)中\(3a1\),\( \dfrac{1}{2} a3\),\(2a2\)成等差数列,则\( \dfrac{{a}_{2016}-{a}_{2017}}{{a}_{2014}-{a}_{2015}} \)等于(    )
              A.\(3\)或\(-1\)
              B.\(9\)或\(1\)
              C.\(1\)
              D.\(9\)
            • 8.

              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.\(21 \)
            • 9.

              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.\(84\)
            • 10.

              已知数列\(\{a_{n}\}\)为等比数列,\(a_{4}+a_{7}=2\),\(a_{⋅}a_{6}=-8\),则\(a_{1}+a_{10}\)的值为\((\)  \()\)

              A.\(7\)               
              B.\(-5\)         
              C.\(5\)                
              D.\(-7\)
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