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            • 1.
              证明:\( \sqrt {2}\)不是有理数.
            • 2.

              已知曲线\(f(x)= \dfrac{{\log }_{2}(x+1)}{x+1}(x > 0) \)上有一点列\({P}_{n}({x}_{n},{y}_{n})(n∈{N}_{∗}) \),过点\({P}_{n} \)在\(x \)轴上的射影是\({Q}_{n}({x}_{n},0) \),且\({x}_{1}+{x}_{2}+{x}_{3}+⋯{x}_{n}={2}^{n+1}−n−2. (n∈{N}_{∗}) \)

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

              \((2)\)设四边形\({P}_{n}{Q}_{n}{Q}_{n+1}{P}_{n+1} \)的面积是\({S}_{n} \),求\({S}_{n} \)

              \((3)\)在\((2) \)条件下,求证:\(\dfrac{1}{{S}_{1}}+ \dfrac{1}{2{S}_{2}}+⋯+ \dfrac{1}{n{S}_{n}} < 4. \)

            • 3.

              曲线\(y=\sqrt{x}\)上点\({{P}_{1}},{{P}_{2}},\cdots {{P}_{n}}\)与\(x\)轴上点\({{Q}_{1}},{{Q}_{2}},\cdots {{Q}_{n}}\)构成一列正三角形,即\(\Delta O{{P}_{1}}{{Q}_{1}},\Delta {{Q}_{1}}{{P}_{2}}{{Q}_{2}},\cdots \Delta {{Q}_{n-1}}{{P}_{n}}{{Q}_{n}}\),设\(\Delta O{{P}_{1}}{{Q}_{1}}\)的边长为\({{a}_{1}}\),正三角形\(\Delta {{Q}_{n-1}}{{P}_{n}}{{Q}_{n}}\)的边长为\({{a}_{n}}\)


              \((1)\)求\({{a}_{1}},{{a}_{2}}\)

              \((2)\)求数列\(\left\{ {{a}_{n}} \right\}\)的通项公式

              \((3)\)证明:\(\dfrac{1}{{{a}_{1}}^{2}}+\dfrac{1}{{{a}_{2}}^{2}}+\cdots +\dfrac{1}{{{a}_{n}}^{2}} < \dfrac{63}{16}\)

            • 4. 已知函数\(f(x){=}x{-}1{-}a\ln x\).
              \((1)\)若\(f(x){\geqslant }0\),求\(a\)的值;
              \((2)\)设\(m\)为整数,且对于任意正整数\(n{,}(1{+}\dfrac{1}{2})(1{+}\dfrac{1}{2^{2}}){…}(1{+}\dfrac{1}{2^{n}}){ < }m\),求\(m\)的最小值.
            • 5.

              已知函数\(f(x)=\dfrac{m\ln x+n}{{{e}^{x}}}\) \((m\)、\(n\)为常数,\(e= 2.718 28…\)是自然对数的底数\()\),曲线\(y=f(x)\)在点\((1,f(1))\)处的切线方程是\(y=\dfrac{2}{e}\).

              \((1)\)求\(m\)、\(n\)的值;

              \((2)\)求\(f(x)\)的最大值;

              \((3)\)设\(g(x)={f}{{{'}}}(x)\cdot \dfrac{{{e}^{x}}\ln (x+1)}{2}\) \((\)其中\({f}{{{'}}}(x)\)为\(f(x)\)的导函数\()\),证明:对任意\(x > 0\),都有\(g(x) < 1+{{e}^{-2}}.\)  \((\)注:\({{\left[ \ln (x+1) \right]}^{\prime }}=\dfrac{1}{x+1})\)

            • 6.

              利用数学归纳法证明:\( \dfrac{1}{n+1}+ \dfrac{1}{n+2}+…+ \dfrac{1}{3n} > \dfrac{5}{6}(\)\(n\)\(\geqslant 2\),\(n\)\(∈N_{+}).\)

            • 7.

              设数列\(\{a_{n}\}\)满足:\(a_{1}=1\),\({a}_{n+1}={a}_{n}+ \dfrac{1}{{a}_{n}} (n∈N*)\).

              \((\)Ⅰ\()\)证明:\(a_{n} < a_{n+1}(n∈N*)\);

              \((\)Ⅱ\()\)证明:\( \sqrt{2n-1}\leqslant {a}_{n}\leqslant \sqrt{3n-2} (n∈N*)\);

              \((\)Ⅲ\()\)求正整数\(m\),使\(|a_{2017}-m|\)最小.

            • 8.

              己知数列\(\{a_{n}\}\),\(a_{1}=1\),\(a_{n+1} > a_{n}\),\((a_{n}+a_{n+1}-1)^{2}=4a_{n}a_{n+1}(n∈N^{*}).\)

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

              \((2)\)记\({{b}_{n}}=\dfrac{1}{\sqrt[4]{{{a}_{n}}}}\),\(T_{n}=b_{1}+b_{2}+…+b_{n}\),估算\(T_{2017}\)的整数部分.

              \((\)参考数据:\(1.41 < \sqrt{2} < 1.42\),\(44.92 < \sqrt{2018} < 45)\)

            • 9.

              设函数\(f\)\((\)\(x\)\()=\dfrac{1-x}{ax}+\ln x\)在\([1,+∞)\)上为增函数\(.\)  

              \((1)\)求正实数\(a\)的取值范围;

              \((2)\)比较\( \dfrac{1}{n} \)与\(\ln \dfrac{n}{n-1}\left(n∈{N}^{*},n\geqslant 2\right) \)的大小,说明理由;

              \((3)\)求证:\(\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}+\cdots +\dfrac{1}{n} < \ln n(\)\(n∈N\)\(*\), \(n\)\(\geqslant 2)\)

            • 10.

              已知函数\(f(x)={{e}^{x}}-a(x+1)\)\(x=\ln 2\)处的切线的斜率为\(1.(e\)为无理数,\(e=2.71828… )\)

              \((1)\)求\(a\)的值及\(f(x)\)的最小值;

              \((2)\)当\(x\geqslant 0\)时,\(f(x)\geqslant m{{x}^{2}}\)恒成立,求\(m\)的取值范围;

              \((3)\)求证:\(\sum\limits_{i=2}^{n}{\dfrac{\ln i}{{{i}^{4}}}} < \dfrac{1}{2e}(i,n\in {{N}_{+}}).(\)参考数据:\(\ln 2\approx 0.6931)\)

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