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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______.

            • 4.

              已知数列\(\{a_{n}\}\)满足\(a_{1}=2\),\(a_{n}=- \dfrac{1}{a_{n-1}+1}(n\geqslant 2\)且\(n∈N^{*})\),若数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),则\(S_{2\;018}=\)________.

            • 5.

              \((1)\)计算定积分\(∫_{−1}^{2} \sqrt{4−{x}^{2}}dx= \)________.

              \((2)\)设变量\(x\),\(y\)满足不等式组\(\begin{cases} & x+y-4\leqslant 0 \\ & x-3y+3\leqslant 0 \\ & x\geqslant 1 \end{cases}\),则\(z=\dfrac{|x-y-4|}{\sqrt{2}}\)的取值范围是________.

              \((3)\)已知椭圆\(\dfrac{{{x}^{2}}}{{{a}^{2}}}+\dfrac{{{y}^{2}}}{{{b}^{2}}}=1(a > b > 0)\)的左、右焦点分别为\(F_{1}(-c,0)\),\(F_{2}(c,0)\),若椭圆上存在点\(P\)使\(\dfrac{a}{\sin \angle P{{F}_{1}}{{F}_{2}}}=\dfrac{c}{\sin \angle P{{F}_{2}}{{F}_{1}}}\)成立,则该椭圆的离心率的取值范围为________.

              \((4)\)用\(g(n)\)表示自然数\(n\)的所有因数中最大的那个奇数,例如:\(9\)的因数有\(1\),\(3\),\(9\),\(g(9)=9\),\(10\)的因数有\(1\),\(2\),\(5\),\(10\),\(g(10)=5\),那么\(g(1)+g(2)+g(3)+…+g(2^{2015}-1)=\)________.

            • 6.

              设等差数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),若\(a_{2}+a_{4}+a_{9}=24\),则\(\dfrac{{{S}_{{8}}}}{{8}}\cdot \dfrac{{{S}_{{10}}}}{{10}}\)的最大值为__________.

            • 7.

              已知数列\(\{a_{n}\}\)满足\(a_{1}=m\), \(a_{n+1}=\begin{cases} 2a_{n}\mathrm{{,}}n{=}2k\mathrm{{-}}1\mathrm{{,}} \\ a_{n}{+}r\mathrm{{,}}n{=}2k \end{cases}(k∈N^{*},r∈R)\),其前\(n\)项和为\(S_{n}.\)若对任意的\(n∈N^{*}\),数列\(\{a_{n}\}\)都满足\(a_{n+2}=a_{n}\),则\(m\)与\(r\)满足的关系为____\(.\) 

            • 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.

              已知数列\(\{a_{n}\}\)满足\(a_{1}=1\),\({a}_{n+1}= \dfrac{{{a}_{n}}}{{{a}_{n}}+2}(n∈N^{*}).\)若\(b_{n+1}=(n-2λ)( \dfrac{1}{{a}_{n}} +1)\),\((n∈N^{*})\),\(b_{1}=-λ\),且数列\(\{b_{n}\}\)是单调递增数列,则实数\(λ\)的范围是________.

            • 10.

              已知数列\(\{{a}_{n}\} \)满足\(n{a}_{n+2}-(n+2){a}_{n}=λ({n}^{2}+2n) \),其中\({a}_{1}=1,{a}_{2}=2 \),若\({a}_{n} < {a}_{n+1} \)对\(∀n∈{N}^{*} \)恒成立,则实数\(λ \)的取值范围为__________.

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