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            • 1.

              设\({f}{{{"}}}(x)\)是函数\(f(x)\)定义在\((0,+\infty )\)上的导函数,满足\(x{f}{{{"}}}(x)+2f(x)=\dfrac{1}{{{x}^{2}}}\),则下列不等式一定成立的是


              A.\(\dfrac{f(e)}{{{e}^{2}}} > \dfrac{f({{e}^{2}})}{e}\)
              B.\(\dfrac{f(e)}{{{e}^{2}}} < \dfrac{f(3)}{9}\)  

              C.\(\dfrac{f(2)}{{{e}^{2}}} > \dfrac{f(e)}{4}\)
              D.\(\dfrac{f(2)}{9} < \dfrac{f(3)}{4}\)
            • 2.

              \((1)\)设\(a= \sqrt{3}+2 \sqrt{2}\),\(b=2+ \sqrt{7}\),则\(a\),\(b\)的大小关系为______.

              \((2)\) 某设备的使用年数\(x\)与所支出的维修总费用\(y\)的统计数据如下表:

              使用年数\(x(\)单位:年\()\)

              \(2\)

              \(3\)

              \(4\)

              \(5\)

              \(6\)

              维修总费用\(y(\)单位:万元\()\)

              \(1.5\)

              \(4.5\)

              \(5.5\)

              \(6.5\)

              \(7.0\)

              根据上标可得回归直线方程为\( \overset{\}{y} =1.3x+ \overset{\}{a} \),若该设备维修总费用超过\(12\)万元,据此模型预测该设备最多可使用______ 年.

              \((3)\)给出下列不等式:\(1+\dfrac{1}{2}+\dfrac{1}{3} > 1\),\(1+\dfrac{1}{2}+\dfrac{1}{3}+\ldots +\dfrac{1}{7} > \dfrac{3}{2}\),\(1+\dfrac{1}{2}+\dfrac{1}{3}+\ldots +\dfrac{1}{15} > 2…\),则按此规律可猜想第\(n\)个不等式为______ .

              \((4)\)复数\({Z}_{1},{Z}_{2} \)分别对应复平面内的点\({M}_{1},{M}_{2} \),且\(\left| {{Z}_{1}}+{{Z}_{2}} \right|=\left| {{Z}_{1}}-{{Z}_{2}} \right|\),线段\({{M}_{1}}{{M}_{2}}\)的中点\(M\)对应的复数为\(4+3i\),则\({{\left| {{Z}_{1}} \right|}^{2}}+{{\left| {{Z}_{2}} \right|}^{2}}=\)________.

            • 3.

              已知\(|x_{1}-2| < 1\),\(|x_{2}-2| < 1\),\({{x}_{1}}\ne {{x}_{2}}\)

              \((1)\)求证:\(2 < x\)\({\,\!}_{1}\)\(+x\)\({\,\!}_{2}\)\( < 6\),\(|x\)\({\,\!}_{1}\)\(-x\)\({\,\!}_{2}\)\(| < 2;\)

              \((2)\)若\(f(x)=x\)\({\,\!}^{2}\)\(-x+1\),求证:\(|x\)\({\,\!}_{1}\)\(-x\)\({\,\!}_{2}\)\(| < |f(x\)\({\,\!}_{1}\)\()-f(x\)\({\,\!}_{2}\)\()| < 5|x\)\({\,\!}_{1}\)\(-x\)\({\,\!}_{2}\)\(|.\)

            • 4. 设\(a{,}b\)为正实数,现有下列陈述:
              \({①}\)若\(a^{2}{-}b^{2}{=}1\),则\(a{-}b{ < }1\);
              \({②}\)若\(\dfrac{1}{b}{-}\dfrac{1}{a}{=}1\),则\(a{-}b{ < }1\);
              \({③}\)若\({|}\sqrt{a}{-}\sqrt{b}{|=}1\),则\({|}a{-}b{|} < 1\);
              \({④}\)若\({|}a^{3}{-}b^{3}{|=}1\),则\({|}a{-}b{|} < 1\).
              其中的正确的有______\({.}(\)写出所有正确陈述的编号\()\)
            • 5.

              设不等式\(0 < \left| x+2 \right|-\left| 1-x \right| < 2\)的解集为\(M\),\(a\),\(b∈M\)

              \((1)\)证明:\(\left| a+\dfrac{1}{2}b \right| < \dfrac{3}{4}\);

              \((2)\)比较\(|4ab-1|\)与\(2|b-a|\)的大小,并说明理由.

            • 6.

              已知\(y=f(x)\)是定义在\(R\)上的偶函数,满足\(f(x+1)=f(1-x)\),且当\(x∈[3,4]\)时,\(f(x)=x-2\) ,则(    )

              A.\(f(\sin \dfrac{1}{2})\leqslant f(\cos \dfrac{1}{2}) \)        
              B.\(f(\sin \dfrac{π}{3}) > f(\cos \dfrac{π}{3}) \)
              C.\(f(\sin 1) < f(\cos 1)\)               
              D.\(f(\sin \dfrac{3}{2}) > f(\cos \dfrac{3}{2}) \) 
            • 7.

              选修\(4-4\) 不等式选讲

               设不等式\(-2 < \left|x-1\right|-\left|x+2\right| < 0 \)的解集为\(M \),且\(a,b∈M \)

              \((1)\)  证明:\(\left| \dfrac{1}{3}a+ \dfrac{1}{6}b\right| < \dfrac{1}{4} \); \((2)\)比较\(\left|1-4ab\right| \)与\(2\left|a-b\right| \)的大小,并说明理由。

            • 8.

              已知\(f{{"}}\left( x \right)\)是定义在\(\left( 0,+\infty \right)\)上的函数\(f\left( x \right)\)的导函数,若方程\(f{{"}}\left( x \right)=0\)无解,且\(\forall x\in \left( 0,+\infty \right)\),\(f\left[ f\left( x \right)-{lo}{{{g}}_{2016}}x \right]=2017\),设\(a=f\left( {{2}^{0.5}} \right)\),\(b=f\left( {lo}{{{g}}_{\pi }}3 \right)\),\(c=f\left( {lo}{{{g}}_{4}}3 \right)\),则\(a\),\(b\),\(c\)的大小关系是\((\)  \()\)

              A.\(b > c > a\)
              B.\(a > c > b\)
              C.\(c > b > a\)
              D.\(a > b > c\)
            • 9.

              使不等式\( \sqrt{3}+ \sqrt{8} > 1+ \sqrt{a} \)成立的正整数\(a\)的最大值是          .

            • 10.
              若\(a > b > 0\),\(m > 0\),判断\( \dfrac {b}{a}\)与\( \dfrac {b+m}{a+m}\)的大小关系,
              并加以证明.
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