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            • 1.

              \((1) \overset{⇀}{a}=\left(x,3\right)\;,\; \overset{⇀}{b}=\left(2\;,\;-1\right) \) ,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________________.

            • 2. 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\(S_{n}\).

            • 3.

              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.

            • 4.
              设数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),已知\(a_{1}= \dfrac{1}{3}\),且对任意正整数\(m\),\(n\)都有\(a_{m+n}=a_{m}·a_{n}\),若\(S_{n} < \) \(a\)恒成立,则实数 \(a\)的最小值为________.
            • 5.

              将正整数\(12\)分解成两个正整数的乘积有\(1×12\),\(2×6\),\(3×4\)三种,其中\(3×4\)是这三种分解中两数差的绝对值最小的,我们称\(3×4\)为\(12\)的最佳分解\(.\) 当\(p×q(p\leqslant q\)且\(p\),\(q∈N^{*})\)是正整数\(n\)的最佳分解时,我们定义函数\(f(n)=q-p\),例如\(f(12)=4-3=1\),数列\(\left\{ f\left( 3^{n} \right) \right\}\)的前\(100\)项和为____\(.\) 

            • 6.

              已知等比数列\(\{a_{n}\}\)的公比为\(q\),前\(n\)项和为\(S_{n}\),若点\((n,S_{n})\)在函数\(y=2^{x+1}+m\)的图象上,则\(m=(\)  \()\)

              A.\(-2\)                                                         
              B.\(2\)

              C.\(-3\)                                                          
              D.\(3\)
            • 7.

              已知数列\(\{ a_{n}\}\)与\(\{ b_{n}\}\)的前\(n\)项和分别是\(S_{n}\)和\(T_{n}\),已知\(S_{100}{=}41{,}T_{100}{=}49\),记\(C_{n}{=}a_{n}T_{n}{+}b_{n}S_{n}{-}a_{n}b_{n}(n{∈}N^{{*}})\),那么数列\(\{ C_{n}\}\)的前\(100\)项和\(\sum_{i{=}1}^{100}C_{i}{=}\) ______ .

            • 8.

              \((1)\)实数\(x\),\(y\)满足\(\begin{cases}x\leqslant 3 \\ x+y\geqslant 0 \\ x-y-2\geqslant 0\end{cases} \),则\(z=y-2x\)的最小值为_____.

              \((2)\)等比数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),\({a}_{1}=- \dfrac{1}{2} \),若\(\dfrac{{S}_{6}}{{S}_{3}}= \dfrac{7}{8} \), 则\(a_{2}·a_{4}=\)____.

              \((3)\)通常,满分为\(100\)分的试卷,\(60\)分为及格线\(.\)若某次满分为\(100\)分的测试卷,\(100\)人参加测试,将这\(100\)人的卷面分数按照\([24,36)\),\([36,48)\),\(...\),\([84,96]\)分组后绘制的频率分布直方图如图所示\(.\)由于及格人数较少,某位老师准备将每位学生的卷面得分采用“开方乘以\(10\)取整”的方法进行换算以提高及格率\((\)实数\(a\)的取整等于不超过\(a\)的最大整数\()\),如:某位学生卷面\(49\)分,则换算成\(70\)分作为他的最终考试成绩,则按照这种方式,这次测试的及格率将变为_______.


              \((4)\)在平面直角坐标系\(xOy\)中,\(O\)为坐标原点,动点\(M\)到点\(P(1,0)\)与到点\(Q(4,0)\)的距离之比为\(\dfrac{1}{2} \),已知点\(A(\sqrt{2} ,0)\),则\(∠OMA\)的最大值为______.

            • 9.

              设数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),若对于任意的\(n∈N^{*}\),都有\(S_{n}=2a_{n}-3n\).

                  \((1)\)求数列\(\{a_{n}\}\)的首项与递推关系式\(a_{n+1}=f(a_{n})\);

                  \((2)\)先阅读下面定理,若数列\(\{a_{n}\}\)有递推关系\(a_{n+1}=Aa_{n}+B\),其中,\(A\)、\(B\)为常数,且\(A\neq 1\),\(B\neq 0\),则数列\(\{{{a}_{n}}-\dfrac{B}{{1}-A}\}\)是以\(A\)为公比的等比数列,请你在第\((1)\)题的基础上应用本定理,求数列\(\{a_{n}\}\)的通项公式;

                  \((3)\)求数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}\).

            • 10. 在等比数列\(\{a_{n}\}\)中,已知\(a_{1}=2\),\(a_{2}a_{3}=32\),则数列\(\{a_{n}\}\)的前\(6\)项和\(S_{6}=(\)  \()\)
              A.\(62\)
              B.\(64\)
              C.\(126\)
              D.\(128\)
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