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            • 1.

              已知等差数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}\)满足\(S_{3}=0\),\(S_{5}=-5\).

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

              \((\)Ⅱ\()\)求数列\(\{\)\(\}\)的前\(n\)项和.


            • 2.

              已知 \(\{{a}_{n}\} \) 为等差数列,前\(n\)项和为 \(S_{n}(n\)\(∈N*\)\()\) \(\{{b}_{n}\} \) 是首项为\(2\)的等比数列,且公比大于\(0\), \(b_{2}+b_{3}=12\)  \(b_{3}=a_{4}-2a_{1}\)  \(S_{11}=11b_{4}\) 

              \((\)Ⅰ\()\)求 \(\{{a}_{n}\} \) \(\{{b}_{n}\} \) 的通项公式;

              \((\)Ⅱ\()\)求数列 \(\{a_{2n}b_{2n-1}\}\) 的前\(n\)项和 \((n\)\(∈N*\)\()\)

            • 3.

              在数列\(\{a_{n}\}\),\(\{b_{n}\}\)中,已知\(a_{1}=0\),\(a_{2}=1\),\(b_{1}=1\),\(b_{2}=\dfrac{1}{2}\),数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),数列\(\{b_{n}\}\)的前\(n\)项和为\(T_{n}\),且满足\(S_{n}+S_{n+1}=n^{2}\),\(2T_{n+2}=3T_{n+1}-T_{n}\),其中\(n\)为正整数.

              \((1)\) 求数列\(\{a_{n}\}\),\(\{b_{n}\}\)的通项公式.

              \((2)\) 问:是否存在正整数\(m\),\(n\),使得\(\dfrac{T_{n{+}1}\mathrm{{-}}m}{T_{n}\mathrm{{-}}m} > 1+b_{m+2}\)成立\(?\)若存在,求出所有符合条件的有序实数对\((m,n);\)若不存在,请说明理由.

            • 4. 数列\(\{a_{n}\}\)满足\(a_{1}=1\),\( \dfrac {1}{2a_{n+1}}= \dfrac {1}{2a_{n}}+1(n∈N^{*}).\)
              \((\)Ⅰ\()\)求证\(\{ \dfrac {1}{a_{n}}\}\)是等差数列;
              \((\)Ⅱ\()\)若\(b_{n}=a_{n}⋅a_{n+1}\),求\(\{b_{n}\}\)的前\(n\)项和\(S_{n}\).
            • 5.

              \((1)\)在二项式\((ax^{2}+ \dfrac{1}{ \sqrt{x}} )^{5}\)的展开式中,若常数项为\(-10\),则\(a=\)__________.

              \((2)\)在一个容量为\(5\)的样本中,数据均为整数,已测出其平均数为\(10\),但墨水污损了两个数据,其中一个数据的十位数字\(1\)未污损,即\(9\),\(10\),\(11\),,那么这组数据的方差\(s^{2}\)可能的最大值是__________.

              \((3)\)如图,抛物线\(y^{2}=4x\)的一条弦\(AB\)经过焦点\(F\),取线段\(OB\)的中点\(D\),延长\(OA\)至点\(C\),使\(|OA|=|AC|\),过点\(C\),\(D\)作\(y\)轴的垂线,垂足分别为\(E\),\(G\),则\(|EG|\)的最小值为__________.


              \((4)\)在数列\(\{a_{n}\}\)中,\(a_{1}=1\),\(a_{n}= \dfrac{{n}^{2}}{{n}^{2}-1} a_{n-1}(n\geqslant 2,n∈N^{*})\),则数列\(\{ \dfrac{{a}_{n}}{{n}^{2}} \}\)的前\(n\)项和\(T_{n}=\)__.

            • 6. 设数列\(\{a_{n}\}\)首项\(a_{1}=2\),前\(n\)项和为\(S_{n}\),且满足\(2a_{n+1}+S_{n}=3(n∈N^{*})\),则满足\( \dfrac {34}{33} < \dfrac {S_{2n}}{S_{n}} < \dfrac {16}{15}\)的所有\(n\)的和为______
            • 7.

              已知数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项之和为\({{S}_{n}}\)满足\({{S}_{n}}=2{{a}_{n}}-2\).

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

               \((\)Ⅱ\()\)求数列\(\left\{ (2n-1)\cdot {{a}_{n}} \right\}\)的前\(n\)项和\({{T}_{n}}\).

            • 8.

              设\(S_{n}\)为数列\(\{a_{n}\}\)的前\(n\)项和,若不等式\({{n}^{2}}a_{n}^{2}+4S_{n}^{2}\geqslant \lambda {{n}^{2}}a_{1}^{2}\)对任意等差数列\(\{a_{n}\}\)及任意正整数\(n\)恒成立,则\(λ\)的最大值为________.

            • 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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