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            • 1.

              数列\(\{a_{n}\}\)满足\(a_{1}=1\),且\(a_{n+1}=a_{1}+a_{n}+n(n∈N^{*})\),则\( \dfrac{1}{a_{1}}+ \dfrac{1}{a_{2}}+…+ \dfrac{1}{a_{2 016}}\)等于\((\)  \()\)

              A.\( \dfrac{4 032}{2 017}\)
              B.\( \dfrac{4 028}{2 015}\)

              C.\( \dfrac{2 015}{2 016}\)
              D.\( \dfrac{2 014}{2 015}\)
            • 2.

              \((1)\)已知等差数列\(\left\{ a_{n} \right\}\)中,公差\(d{\neq }0\),且\(a_{1}\),\(a_{3}\),\(a_{9}\)成等比数列,求\(\dfrac{a_{1}{+}a_{3}{+}a_{9}}{a_{2}{+}a_{4}{+}a_{10}}{=}\)___.

              \((2)\)平面\(\alpha\)过正方体\(ABCD{-}A_{1}B_{1}C_{1}D_{1}\)的顶点\(A\),\(\alpha{/\!/}\)平面\(CB_{1}D_{1}\),\(\alpha{∩}\)平面\(ABCD{=}m\),\(\alpha{∩}\)平面\({AB}B_{1}A_{1}{=}n\),则\(m{,}n\)所成角的大小为______________.

              \((3)\)一轮船向正北方向航行,某时刻在\(A\)处测得灯塔\(M\)在正西方向且相距\(20\sqrt{3}\)海里,另一灯塔\(N\)在北偏东\({{30}^{\circ }}\)方向,继续航行\(20\)海里至\(B\)处时,测得灯塔\(N\)在南偏东\({{60}^{\circ }}\)方向,则两灯塔\(MN\)之间的距离是__________海里.

              \((4)\)设抛物线\({{y}^{2}}=2x\)的焦点为\(F\),过点\(M\left( \sqrt{3},0 \right)\)的直线与抛物线相交于\(A,B\)两点,与抛物线的准线相交于点\(C\),\(\left| BF \right|=2\),则\(\Delta BCF\)与\(\Delta ACF\)的面积之比\(\dfrac{{{S}_{\Delta BCF}}}{{{S}_{\Delta ACF}}}=\)__________.

            • 3.

              设各项均为正数的数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和为\({{S}_{n}}\),满足\(4{{S}_{n}}=a_{^{_{n+1}}}^{2}-4n-1\),且\({{a}_{1}}=1\),公比大于\(1\)的等比数列\(\left\{ {{b}_{n}} \right\}\)满足\({{b}_{2}}=3\),\({{b}_{1}}+{{b}_{3}}=10\).

              \((1)\)求证数列\(\left\{ {{a}_{n}} \right\}\)是等差数列,并求其通项公式;

              \((2)\)若\({{c}_{n}}=\dfrac{{{a}_{n}}}{3{{b}_{n}}}\),求数列\(\left\{ {{c}_{n}} \right\}\)的前\(n\)项和\({{T}_{n}}\);

              \((3)\)在\((2)\)的条件下,若\({{c}_{n}}\leqslant {{t}^{2}}+\dfrac{4}{3}t-2\)对一切正整数\(n\)恒成立,求实数\(t\)的取值范围.

            • 4.

              当\(n\geqslant 2\)时,\( \dfrac{1}{n^{2}-1}= \dfrac{1}{2}\left( \left. \dfrac{1}{n-1}- \dfrac{1}{n+1} \right. \right).(\)  \()\)

              A.\(√\)  
              B.\(×\)
            • 5.

              设\(M\subseteq {{N}^{+}}\),正项数列\(\{{{a}_{n}}\}\)的前\(n\)项的积为\({{T}_{n}}\),且\(\forall k\in M\),当\(n > k \)时,\(\sqrt{{{T}_{n+k}}{{T}_{n-k}}}={{T}_{n}}{{T}_{k}}\)都成立.

              \((1)\)若\(M=\{1\}\),\({{a}_{1}}=\sqrt{3}\),\({{a}_{2}}=3\sqrt{3}\),求数列\(\{{{a}_{n}}\}\)的前\(n\)项和;

              \((2)\)若\(M=\{3,4\}\),\({{a}_{1}}=\sqrt{2}\),求数列\(\{{{a}_{n}}\}\)的通项公式.

            • 6.

              数列\(\left\{ {{a}_{n}} \right\}\)中,已知\({a}_{n}= \dfrac{{n}^{2}+n-1}{3},(n∈{N}^{*}) \)。

              \((1)\)写出\({a}_{10},{a}_{n+1} \);

              \((2)79 \dfrac{2}{3} \)是否是数列中的项?如果是,是第几项?

            • 7.

              \({{a}_{n}}=2{{n}^{2}}-n\),以下四个数是数列\(\left\{ {{a}_{n}} \right\}\)中的一项的是(    )

              A.\(30\)
              B.\(44\)
              C.\(66\)
              D.\(90\)
            • 8.

              设等差数列\(\left\{ a_{n} \right\}\)的前\(n\)项和为\(S_{n}\),若\(a_{1}{=-}11\),\(a_{4}{+}a_{6}{=-}6\),则当\(S_{n}\)取最小值时,\(n\)等于(    )

              A.\(9\)   
              B.\(8\)   
              C.\(7\)   
              D.\(6\)
            • 9.

              若等差数列\(\{a_{n}\}\)满足\(a_{1}+a_{3}=-2\),\(a_{2}+a_{4}=10\),则\(a_{5}+a_{7}\)的值是\((\)  \()\)


              A.\(-22\)   
              B.\(22\)   
              C.\(-46\)   
              D.\(46\)
            • 10.

              在数列\(\{{{a}_{n}}\}\)中,\({{a}_{1}}=4,{{a}_{n+1}}-1=3({{a}_{n}}-1)\) ,则数列\(\left\{ {{a}_{n}} \right\}\)的通项公式\({{a}_{n}}=\) ______.

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