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            • 1.

              在棱长为\(1\)的正方体\({A} {B} {CD}-{{{A} }_{1}}{{{B} }_{1}}{{{C}}_{1}}{{{D}}_{1}}\)中,\(\text{M} \)是\({{{A} }_{1}}{{{D}}_{1}}\)的中点,点\({R} \)在侧面\({B} {C}{{{C}}_{1}}{{{B} }_{1}}\) 上运动\(.\)现有下列命题:


              \(①\)若点\({R} \)总保持\({R} {A} \bot {B} {{{D}}_{1}}\),则动点\({R} \)的轨迹所在的曲线是直线;

              \(②\)若点\({R} \)到点\({A} \)的距离为\(\dfrac{2\sqrt{3}}{3}\),则动点\({R} \)的轨迹所在的曲线是圆;

              \(③\)若\({R} \)满足\(\angle \text{M} {A} {R} =\angle \text{M} {A} {{{C}}_{1}}\),则动点\({R} \)的轨迹所在的曲线是椭圆;

              \(④\)若\({R} \)到直线\({B} {C}\)与直线\({{{C}}_{1}}{{{D}}_{1}}\)的距离比为\(2:1\),则动点\({R} \)的轨迹所在的曲线是双曲线;

              其中真命题的序号为_________________        

            • 2.

              \((1)\)抛物线\({{y}^{2}}=ax(a > 0)\)上的点\(P(\dfrac{3}{2},{{y}_{0}})\)到焦点\(F\)的距离为\(2\),则\(a=\)_________.

              \((2)\)已知递减等差数列\(({{a}_{n}})\)中,\({{a}_{3}}=-1,{{a}_{4}}\)为\({{a}_{1}},-{{a}_{6}}\)等比中项,若\({{S}_{n}}\)为数列\(({{a}_{n}})\)的前\(n\)项和,则\({{S}_{7}}\)的值为_________.

              \((3)\)在四面体\(S-ABC\)中,\(AB\bot BC,AB=BC=\sqrt{2},SA=SC=2\),二面角\(S-AC-B\)的余弦值是\(-\dfrac{\sqrt{3}}{3}\),则该四面体的外接球的表面积是_________.

              \((4)\)设函数\(f(x)=\dfrac{{{x}^{2}}+1}{x},g(x)=\dfrac{x}{{{e}^{x}}},\)对任意\({{x}_{1}},{{x}_{2}}\in (0,+\infty ),\)不等式\(\dfrac{g({{x}_{1}})}{k}\leqslant \dfrac{f({{x}_{2}})}{k+1}\)恒成立,则正数\(k\)的取值范围是_________.

            • 3.
              在球\(O\)的内接四面体\(A-BCD\)中,\(AB=6\),\(AC=10\),\(∠ABC= \dfrac {π}{2}\),且四面体\(A-BCD\)体积的大值为\(200\),则球\(O\)的半径为 ______ .
            • 4.
              在三棱锥\(A-BCD\)中,\(AB⊥\)平面\(BCD\),\(AB=BC=CD= \sqrt {2}\),\(BC⊥CD\),则该三棱锥的外接球的体积为 ______ .
            • 5.
              四棱锥\(P-ABCD\)的五个顶点都在半径为\( \sqrt {3}\)的半球面上,底面\(ABCD\)是边长为\(2\)的正方形,则顶点\(P\)到平面\(ABCD\)距离的最大值为 ______ .
            • 6.

              \((1)\)将\(a= \sqrt{5}- \sqrt{3} \),\(b=2^{0.3}\),\(c=\log _{0.3}2\)按照从小到大排列是________.

              \((2)\)到球心距离为\(3\)的平面截球所得截面圆的面积为\(16π\),则该球的半径为________.

              \((3)\)设函数\(f(x)=\begin{cases}{2}^{x},(x\leqslant 0), \\ {\log }_{2}x,(x > 0)\end{cases} \)函数\(y=f[f(x)]-1\)的零点个数为________.

              \((4)\)设\(min\{a,b\}=\begin{cases}a,a\leqslant b, \\ b,a > b,\end{cases} \)若函数\(f(x)=min\{-{\log }_{2}x,x+ \dfrac{1}{2}\} \),则\(f(x) < \dfrac{1}{2} \)的解集为________.

            • 7.

              平面\(α\)截半径为\(2\)的球\(O\)所得的截面圆的面积为\(π\),则球心到\(O\)平面\(α\)的距离为     

            • 8.

              \((1)\)公比为\(2\)的等比数列\(\{a_{n}\}\)的各项都是正数,且\(a_{3}⋅a_{11}=16\),则\(a_{5}=\)___.

              \((2)\)不共线向量\( \overrightarrow{a} \),\( \overrightarrow{b} \)满足\(| \overrightarrow{a} |=| \overrightarrow{b} |\),且\( \overrightarrow{a} ⊥( \overrightarrow{a} -2 \overrightarrow{b} )\),则\( \overrightarrow{a} \)与\( \overrightarrow{b} \)的夹角为__.

              \((3)\)若实数\(x\),\(y\)满足\(\begin{cases} & x-y+1\leqslant 0 \\ & x > 0 \\ & y\leqslant 2 \end{cases}\),则\(\dfrac{2y}{2x+1}\)的最小值是__.

              \((4)\)正方体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)外接球半径\( \sqrt{3} \),过\(AC\)作外接球截面,当截面圆最小时,其半径为__.

            • 9.

              \((1)\) 在区间\({[}0{,}4{]}\)上随机取一个数\(x\),则事件“\({-}1{\leqslant }\log_{\frac{1}{2}}(x{+}\dfrac{1}{2}){\leqslant }1\)”发生的概率为______ .

              \((2)A{,}B{,}C{,}D\)是同一球面上的四个点,\({\triangle }ABC\)中,\({∠}BAC{=}\dfrac{2\pi}{3}{,}AB{=}AC{,}AD{⊥}\)平面\({ABC}{,}AD{=}6{,}AB{=}2\sqrt{3}\),则该球的表面积为______ .


              \((3)\) 已知函数\(f(x){=}\dfrac{1}{x{+}1}\),点\(O\)为坐标原点,点\(A_{n}(n{,}f(n))(n{∈}N^{{*}})\),向量\(\overrightarrow{i}{=}(0{,}1){,}\theta_{n}\)是向量\(\overrightarrow{OA_{n}}\)与\(\overrightarrow{i}\)的夹角,则\(\dfrac{\cos\theta_{1}}{\sin\theta_{1}}{+}\dfrac{\cos\theta_{2}}{\sin\theta_{2}}{+…+}\dfrac{\cos\theta_{2017}}{\sin\theta_{2017}}\)的值为______ .

              \((4)\)在四边形\(ABCD\)中,若\(AB{=}2{,}BC{=}2\sqrt{2}{,}AD{=}\sqrt{2}{CD}{,}\overrightarrow{{AC}}\overrightarrow{{⋅}CD}{=}0\),则\({|}\overrightarrow{{BD}}{|}\)的最大值为______ .

            • 10.

              已知球\(O\)的半径为\(R\),\(A\),\(B\),\(C\)三点在球\(O\)的球面上,球心\(O\)到平面\(ABC\)的距离为\(\dfrac{\sqrt{3}R}{2},\),\(AB=AC=BC-2 \sqrt{3} \),则球\(O\)的表面积为_________.

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