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            • 1.

              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                   

            • 2.

              已知数列\(\left\{ {{a}_{n}} \right\}\)的通项公式\({{a}_{n}}=-n+t\),数列\(\left\{ {{b}_{n}} \right\}\)的通项公式\({{b}_{n}}={{2}^{n}}\),设数列\(\left\{ {{c}_{n}} \right\}\)满足\({{c}_{n}}=\dfrac{{{a}_{n}}+{{b}_{n}}}{2}+\dfrac{\left| {{a}_{n}}-{{b}_{n}} \right|}{2}\),且\({{c}_{n}}\geqslant {{c}_{3}}\left( n\in {{N}^{{*}}} \right)\),则实数\(t\)的取值范围是________________

            • 3. 已知数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(a_{1}=1\),\(a_{n+1}= \dfrac {1}{2}S_{n}\),则\(a_{5}=(\)  \()\)
              A.\( \dfrac {1}{16}\)
              B.\( \dfrac {1}{8}\)
              C.\( \dfrac {27}{16}\)
              D.\( \dfrac {81}{16}\)
            • 4.

              已知数列\(\{{{a}_{n}}\}\)的前\(n\)项和为\({{S}_{n}}\),且有\({{a}_{1}}=2\),\(3{{S}_{n}}=5{{a}_{n}}-{{a}_{n-1}}+3{{S}_{n-1}}(n\geqslant 2)\).

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

              \((2)\)若\({{b}_{n}}=(2n-1){{a}_{n}}\),求数列\(\{{{b}_{n}}\}\)的前\(n\)项和\({{T}_{n}}\);

              \((3)\)若\({{c}_{n}}={{t}^{n}}[\lg {{(2t)}^{n}}+\lg {{a}_{n+2}}]{ }(0 < t < 1)\),且数列\(\{{{c}_{n}}\}\)中的每一项总小于它后面的项,求实数\(t\)的取值范围.

            • 5.

              已知函数\(f\left( x \right)=\begin{cases} {{a}^{x-5}},x\geqslant 6, \\ \left( 4-\dfrac{a}{2} \right)x+4,x < 6, \end{cases}\)数列\(\left\{{a}_{n}\right\} \)满足\({{a}_{n}}=f\left( n \right)\left( n\in {{N}^{*}} \right)\),且数列\(\left\{{a}_{n}\right\} \)是递增数列,则实数\(a\)的取值范围是______.

            • 6.

              设数列\(\{a_{n}\}\)是集合\(\{3^{s}+3^{t}|0\leqslant s < t\),且\(S\),\(t∈Z\}\)中所有的数从小到大排列成的数列,即\(a_{1}=4\),\(a_{2}=10\),\(a_{3}=12\),\(a_{4}=28\),\(a_{5}=30\),\(a_{6}=36\),\(…\),将数列\(\{a_{n}\}\)中各项按照上小下大,左小右大的原则排成如图等腰直角三角形数表,\(a_{200}\)的值为\((\)    \()\)

              A.\(3^{9}+3^{19}\)
              B.\(3^{10}+3^{19}\)
              C.\(3^{19}+3^{20}\)
              D.\(3^{10}+3^{20}\)
            • 7.

              已知函数\(f(x)=\dfrac{x+1}{2x-1}\),数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\({{a}_{n}}=f(\dfrac{n}{2017})\),则\(S_{2017}=\)

              A.\(1008\)   
              B.\(1010\)   
              C.\(\dfrac{2019}{2}\)
              D.\(2019\)
            • 8.

              已知对任意\(n∈{N}_{+} \)都有\({a}_{n}=n(n+λ) \)恒成立,且数列\(\{{a}_{n}\} \)是递增数列,则实数\(λ \)的取值范围是____________

            • 9. 设\(f(x)\)是定义在\(R\)上的函数,对任意\(x,y\in R\),都有\(f\left( x+y \right)=f\left( x \right)+f\left( y \right)\),且\(f\left( 1 \right)=1.\)若数列\(\left\{ {{a}_{n}} \right\}\) 满足:\({{a}_{1}}=18,{{a}_{n}}-{{a}_{n-1}}=2f\left( n \right)\),\((n\geqslant 2且n∈{N}^{*}) \),则\(\dfrac{{{a}_{n}}}{n}\)的最小值是(    )
              A.\(7\)
              B.\(9\)
              C.\(\dfrac{15}{2}\)
              D.\(\dfrac{19}{2}\) 
            • 10.
              已知\(f(x)=\ln x,g(x)= \dfrac {1}{2}ax^{2}+3x+1\),\(e\)为自然对数\(\ln x\)的底数.
              \((\)Ⅰ\()\)若函数\(h(x)=f(x)-g(x)\)存在单调递减区间,求实数\(a\)的取值范围;
              \((\)Ⅱ\()\)当\(0 < α < β\)时,求证:\(\alpha f(\alpha )+\beta f(\beta ) > (\alpha +\beta )f( \dfrac {\alpha +\beta }{2})\);
              \((\)Ⅲ\()\)求\(f(x)-x\)的最大值,并证明当\(n > 2\),\(n∈N^{*}\)时,\(\log _{2}e+\log _{3}e+\log _{4}e\cdots +\log _{n}e > \dfrac {3n^{2}-n-2}{2n(n+1)}\).
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