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            • 1.

              设\(\left\{ {{a}_{n}} \right\}\)是公比为\(q\)的等比数列,\(|q| > 1\),令\({{b}_{n}}={{a}_{n}}+1\),若数列\(\left\{ {{b}_{n}} \right\}\)有连续四项在集合\(\left\{ -53,-23,19,37,82 \right\}\)中,则\(q=\)______________.

            • 2.

              在数列\(\left\{ {{a}_{n}} \right\}\)中,\({{a}_{{1}}}{+2}{{a}_{2}}+{{2}^{2}}{{a}_{3}}+\cdots +{{2}^{n-1}}{{a}_{n}}=(n\cdot {{2}^{n}}-{{2}^{n}}+1)\ t\)对任意\(n\in {{N}^{*}}\)成立,其中常数\(t > 0.\)若关于\(n\)的不等式\(\dfrac{1}{{{a}_{2}}}+\dfrac{1}{{{a}_{4}}}+\dfrac{1}{{{a}_{8}}}+\cdots +\dfrac{1}{{{a}_{{{2}^{n}}}}} > \dfrac{m}{{{a}_{1}}}\)的解集为\(\{n|n\geqslant 4,n\in {{N}^{*}}\}\),则实数\(m\)的取值范围是                   

            • 3.

              已知数列\(\{a_{n}\}\)的首项\(a_{1}=1\),前\(n\)项的和为\(S_{n}\),且满足\(2a_{n+1}+S_{n}=2(n∈N^{*})\),则满足\(\dfrac{1\mathrm{\ }001}{1\mathrm{\ }000} < \dfrac{S_{2n}}{S_{n}} < \dfrac{11}{10}\)的\(n\)的最大值为              \(.\) 

            • 4.

              \((1) \overset{⇀}{a}=\left(x,3\right)\;,\; \overset{⇀}{b}=\left(2\;,\;-1\right) \) ,若\( \overset{⇀}{a} \)与\( \overset{⇀}{b} \)的夹角为锐角,则\(x\)的范围是________________.

              \((2)\)数列\(\left\{{a}_{n}\right\} \)的通项公式为\({a}_{n}=2n-1+ \dfrac{1}{{2}^{n}} \),则数列\(\left\{{a}_{n}\right\} \) 的前\(n\)项和为________________.

              \((3)\) 若函数\(f\left(x\right)=\cos 2x+a\sin x \)在区间\(\left( \dfrac{π}{6}\;,\; \dfrac{π}{2}\right) \)上是减函数,则\(a\)的取值范围是________________.

              \((4)\) 设函数\(y=\begin{cases}-{x}^{3}+{x}^{2}\;,\;x < e \\ a\ln x\;,\;x\geqslant e\end{cases} \)的图象上存在两点 \(P\),\(Q\),使得\(∆POQ \)是以\(O\)为直角顶点的直角三角形\((\)其中\(O\)为坐标原点\()\),且斜边的中点恰好在\(y\)轴上,则实数\(a\)的取值范围是________________.

            • 5. 根据如图所示的程序框图,将输出的\(x\),\(y\)依次记为\(x_{1}\),\(x_{2}\),\(…\),\(x_{2016}\),\(y_{1}\),\(y_{2}\),\(…\),\(y_{2016}\).

                  \((1)\)求出数列\(\{x_{n}\}\),\(\{y_{n}\}\)的通项公式;

              \((2)\)求数列\(\{x_{n}+y_{n}\}(n\leqslant 2016)\)的前\(n\)项和\(S_{n}\).

            • 6.\(S_{n}\)为等比数列\(\{ \)\(a_{n}\)\(\}\)的前 \(n\)项和, \(a\)\({\,\!}_{2}-8\) \(a\)\({\,\!}_{5}=0\),则\( \dfrac{S_{8}}{S_{4}}\)的值为(    )
              A.\( \dfrac{1}{2}\)                             
              B.\( \dfrac{17}{16}\)
              C.\(2\)                                       
              D.\(17\)
            • 7. 若等比数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}=(a-2)⋅3^{n+1}+2\),则常数\(a=\) ______ .
            • 8.
              数列\(\{a_{n}\}\)中若\(a_{n+1}=2a_{n}\),且\(a_{2}=4\),则\(S_{4}\)的值等于\((\)  \()\)
              A.\(30\)
              B.\(15\)
              C.\(20\)
              D.\(60\)
            • 9. 设数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),对于所有\(n\geqslant 1\),\(S_{n}= \dfrac {a_{1}(3^{n}-1)}{2}\),且\(a_{4}=54\),则\(a_{1}=\)______.
            • 10. 已知\(\{ \)\(a_{n}\)\(\}\)是公差为\(3\)的等差数列,数列\(\{ \)\(b_{n}\)\(\}\)满足 \(b\)\({\,\!}_{1}=1\), \(b\)\({\,\!}_{2}= \dfrac{1}{3}\), \(a_{n}b_{n}\)\({\,\!}_{+1}+\) \(b_{n}\)\({\,\!}_{+1}=\) \(nb_{n}\)

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

              \((2)\)求\(\{\)\(b_{n}\)\(\}\)的前\(n\)项和.

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