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            • 1.

              用分期付款的方式购买家用电器需\(11500\)元,购买当天先付\(1500\)元,以后每月交付\(500\)元,并加付利息,月利率为\(0.5\%\),若从交付\(1500\)元后的第\(1\)个月开始算分期付款的第\(1\)个月,问:

              \((1)\)分期付款的第\(10\)个月应交付多少钱?

              \((2)\)全部贷款付清后,买家用电器实际花了多少钱?

            • 2.

              设数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),\(S_{n}=n^{2}+n\),数列\(\{b_{n}\}\)的通项公式为\(b_{n}=x^{n-1}\).

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

              \((2)\)设\(c_{n}=a_{n}b_{n}\),数列\(\{c_{n}\}\)的前\(n\)项和为\(T_{n}\).

              \(①\)求\(T_{n}\);

              \(②\)若\(x=2\),求数列\(\{\dfrac{nTn+1-2n}{{{T}_{n+2}}-2}\}\)的最小项的值.

            • 3. 已知数列\(\{ \)\(a_{n}\)\(\}\)的前 \(n\)项和为 \(S_{n}\)\(a_{n}\)\(=\) \(n\)\(·2\) \({\,\!}^{n}\),则 \(S_{n}\)\(=\)________.
            • 4.

              已知数列\(\left\{{b}_{n}\right\} \)是等差数列,\({b}_{1}=1,{b}_{1}+{b}_{2}+…+{b}_{10}=145 \).

              \((1)\)求数列\(\left\{{b}_{n}\right\} \)的通项公式\({b}_{n} \);

              \((2)\)设数列\(\left\{{a}_{n}\right\} \)的通项\({a}_{n}={\log }_{a}\left(1+ \dfrac{1}{{b}_{n}}\right) (\)其中\(a > 0\)且\(a\neq 1 )\)记\({S}_{n} \)是数列\(\left\{{a}_{n}\right\} \)的前\(n\)项和,试比较\({S}_{n} \)与\(\dfrac{1}{3}{\log }_{a}{b}_{n+1} \)的大小,并证明你的结论.

            • 5.

              已知数列\(\{ a_{n}\}\)的前\(n\)项和为\(S_{n}{,}a_{1}{=}\dfrac{1}{2}{,}2a_{n{+}1}{=}S_{n}{+}1\).

              \((\)Ⅰ\()\)求\(a_{2}{,}a_{3}\)的值;

              \((\)Ⅱ\()\)设\(b_{n}{=}2a_{n}{-}2n{-}1\),求数列\(\{ b_{n}\}\)的前\(n\)项和\(T_{n}\).

            • 6.

              在等差数列\(\left\{{a}_{n}\right\} \)中,\({a}_{1}=-2008 \),其前\(n\)项和为\(S_{n}\),若\(\dfrac{{S}_{12}}{12}- \dfrac{{S}_{10}}{10}=2 \),则\(S_{2008}\)的值等于______ .

            • 7.

              在等差数列\(\left\{ {{a}_{n}} \right\}\)中,公差\(d=2,{{a}_{n}}=11,{{S}_{n}}=35\),则\({{a}_{1}}\)等于\((\)  \()\)

              A.\(5\)或\(7\)
              B.\(3\)或\(5\)
              C.\(7\)或\(-1\)
              D.\(3\)或\(-1\)
            • 8.

              若存在常数\(k\left( k\in {{N}^{*}},k\geqslant 2 \right)\)\(q\)\(d\),使得无穷数列\(\left\{ {{a}_{n}} \right\}\)满足\({{a}_{n+1}}=\begin{cases} {{a}_{n}}+d,\dfrac{n}{k}\notin {{N}^{*}} \\ q{{a}_{n}},\dfrac{n}{k}\in {{N}^{*}} \\\end{cases}\)则称数列\(\left\{ {{a}_{n}} \right\}\)为“段比差数列”,其中常数\(k\)\(q\)\(d\)分别叫做段长、段比、段差\(.\)设数\(\left\{ {{b}_{n}} \right\}\)为“段比差数列”,它的首项、段长、段比、段差分别为\(1\)、\(3\)、\(q\)、\(3\).

                \((1)\)当\(q=0\)时,求\({{b}_{2014}}\),\({{b}_{2016}}\);

                \((2)\)当\(q=1\)时,设\(\left\{ {{b}_{n}} \right\}\)的前\(3n\)项和为\({{S}_{3n}}\),

                     \(①\)证明:\(\left\{ {{b}_{3n-1}} \right\}\)为等差数列;

                     \(②\)证明:\({{b}_{3n-2}}+{{b}_{3n}}=2{{b}_{3n-1}}\);

                     \(③\)若不等式\({{S}_{3n}}\leqslant \lambda \cdot {{3}^{n-1}}\)对\(n\in {{N}^{*}}\)恒成立,求实数\(\lambda \)的取值范围;

            • 9. 数列\(\{ \)\(a_{n}\)\(\}\)的前 \(n\)项和为 \(S_{n}\)\(a\)\({\,\!}_{1}=1\), \(S_{n}\)\({\,\!}_{+1}=4\) \(a_{n}\)\(+2( \)\(n\)\(∈N^{*})\),设 \(b_{n}\)\(=\) \(a_{n}\)\({\,\!}_{+1}-2\) \(a_{n}\)

              \((1)\)求证:\(\{\)\(b_{n}\)\(\}\)是等比数列;

              \((2)\)设\(c_{n}\)\(= \dfrac{a_{n}}{3n-1}\),求证:\(\{\)\(c_{n}\)\(\}\)是等比数列.

            • 10.

              设\({{S}_{n}}\)为数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和,已知\({{a}_{1}}=2\) ,对任意\(p,q\in N^{*}\),都有\({{a}_{p+q}}={{a}_{p}}+{{a}_{q}}\),则\(f\left( n \right)=\dfrac{{{S}_{n}}+60}{n+1}(n\in N^{*})\)的最小值为         \(.\) 

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