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            • 1.

              已知\(\{a_{n}\}\)是各项均为正数的等比数列,且\(a_{1}+a_{2} =6\),\(a_{1}a_{2}= a_{3}\).

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

              \((2)\{b_{n}\}\)为各项非零的等差数列,其前\(n\)项和为\(S_{n}.\)已知\(S_{2n+1}=b_{n}b_{n+1}\),求数列\(\left\{ \left. \dfrac{b_{n}}{a_{n}} \right. \right\}\)的前\(n\)项和\(T_{n}\).

            • 2.

              已知数列\(\{a_{n}\}\)是首项为\(1\),公差为\(2\)的等差数列,数列\(\{b_{n}\}\)满足\(\dfrac{{{a}_{{1}}}}{{{b}_{{1}}}}+\dfrac{{{a}_{{2}}}}{{{b}_{{2}}}}+\dfrac{{{a}_{{3}}}}{{{b}_{{3}}}}+\ldots +\dfrac{{{a}_{n}}}{{{b}_{n}}}=\dfrac{{1}}{{{{2}}^{n}}}\),若数列\(\{b_{n}\}\)的前\(n\)项和为\(S_{n}\),则\(S_{5}=\)


              A.\(-454\)
              B.\(-450\)
              C.\(-446\)
              D.\(-442\)
            • 3.

              \((1)\)已知各项均为正数的等比数列\(\{a_{n}\}\)满足\(a_{7}=a_{6}+2a_{5}\),若存在两项\(a_{m}\),\(a_{n}\)使得\( \sqrt{a_{m}a_{n}}=4a_{1}\),则\( \dfrac{1}{m}+ \dfrac{4}{n}\)的最小值为_____________.


              \((2)S_{n}\)为数列\(\{a_{n}\}\)的前\(n\)项和\(.\)已知\(a_{n} > 0\),\(a\rlap{_{n}}{^{2}}+2a_{n}=4S_{n}+3\).

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

              \(②\)设\(b_{n}= \dfrac{1}{a_{n}a_{n+1}}\),求数列\(\{b_{n}\}\)的前\(n\)项和.

            • 4.

              已知\(\{a_{n}\}\)是一个公差大于\(0\)的等差数列,且满足\(a_{3}a_{5}=45\),\(a_{2}+a_{6}=14\).

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

              \((2)\)若数列\(\{b_{n}\}\)满足:\(\dfrac{{{b}_{1}}}{2}+\dfrac{{{b}_{2}}}{{{2}^{2}}}+\ldots +\dfrac{{{b}_{n}}}{{{2}^{n}}}={{a}_{n}}+1(n\in {{N}^{{*}}})\),求\(\{b_{n}\}\)的前\(n\)项和.

            • 5.

              已知数列\(\left\{ {{a}_{n}} \right\}\)中,\({{a}_{n}} > 0\),\({{a}_{1}}=1\),\({{a}_{n+2}}=\dfrac{1}{{{a}_{n}}+1}\),\({{a}_{100}}={{a}_{96}}\),则\({{a}_{2018}}+{{a}_{3}}=(\)   \()\)

              A.\(\dfrac{5}{2}\)
              B.\(\dfrac{1+\sqrt{5}}{2}\)
              C.\(\dfrac{\sqrt{5}}{2}\)
              D.\(\dfrac{-1+\sqrt{5}}{2}\)
            • 6.
              已知数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(S_{n}=2a_{n}+1\),则数列\(\{a_{n}\}\)的通项公式为\((\)  \()\)
              A.\(a_{n}=-2^{n-1}\)
              B.\(a_{n}=2^{n-1}\)
              C.\(a_{n}=2n-3\)
              D.\(a_{n}=2^{n-1}-2\)
            • 7.
              已知数列\(\{a_{n}\}\)满足\(a_{1}=6\),\(a_{n+1}-a_{n}=2n\),记\(c_{n}= \dfrac {a_{n}}{n}\),且存在正整数\(M\),使得对一切\(n∈N^{*}\),\(c_{n}\geqslant M\)恒成立,则\(M\)最大值为\((\)  \()\)
              A.\(3\)
              B.\(4\)
              C.\(5\)
              D.\(6\)
            • 8.

              已知\(f\left(n\right)= \dfrac{1}{n+1}+ \dfrac{1}{n+2}+ \dfrac{1}{n+3}+...+ \dfrac{1}{2n}\left(n∈{N}^{*}\right), \)那么\(f\left(n+1\right)-f\left(n\right) \)等于   \((\)   \()\)

              A.\(\dfrac{1}{2n+1}\)
              B.\(\dfrac{1}{2n+2}\)
              C.\(\dfrac{1}{2n+1}+\dfrac{1}{2n+2}\)
              D.\(\dfrac{1}{2n+1}-\dfrac{1}{2n+2}\)
            • 9.

              已知数列\(\{b_{n}\}\)满足\(b_{1}=1\),且\(16{b}_{n+1}={b}_{n}(n∈{N}^{*}) \),设数列\(\left\{ \sqrt{{b}_{n}}\right\} \)的前\(n\)项和是\(T_{n}\) .

              \((1)\)比较\({{T}_{n+1}}^{2} \)与\({T}_{n}·{T}_{n+2} \)的大小;

              \((2)\)若数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}=2n^{2}+2n+2\),数列\(\{c_{n}\}\)满足\(c_{n}=a_{n}+\log _{d}b\)n\((d > 0,d\neq 1) \),求\(d\)的取值范围,使得数列\(\{c_{n}\}\)是递增数列.

            • 10.

              等比数列中,分别是下表第一、二、三行中的某一个数,且中的任何两个数不在下表的同一列.


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

              \((2)\)若数列\(\{b_{n}\}\)满足:\(b_{n}=a_{n}+(-1)^{n}\ln a_{n}\),求数列的\(2n\)前项和\(S2_{n}\).

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