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            • 1.
              已知正数\(x\)、\(y\)、\(z\)满足\(x^{2}+y^{2}+z^{2}=1\),则\(S= \dfrac {1+z}{2xyz}\)的最小值为\((\)  \()\)
              A.\(3\)
              B.\( \dfrac {3( \sqrt {3}+1)}{2}\)
              C.\(4\)
              D.\(2( \sqrt {2}+1)\)
            • 2. 已知\(a > 0,b > 0,c > 0\),函数\(f(x)=\left| x+a \right|+\left| x-b \right|+c\)的最小值为\(4\).

              \((1)\)求\(a+b+c\)的值;

                    

              \((2)\)求\(\dfrac{1}{4}{{a}^{2}}+\dfrac{1}{9}{{b}^{2}}+{{c}^{2}}\)的最小值
            • 3.

              \((\)不等式选讲\()\)设\(a > 0\),\(b > 0\),\(c > 0\),函数\(f(x)=\left| x+a \right|+\left| x-b \right|+c\)的最小值为\(4\) .

              \((\ \text{I} \ )\) 求\(a+b+c\)的值;

              \(\left( \ \text{I} \text{I} \ \right)\)求\(\dfrac{1}{4}{{a}^{2}}+\dfrac{1}{9}{{b}^{2}}+{{c}^{2}}\)的最小值.

            • 4.

              已知函数\(f(x)=a\ln x+\dfrac{1}{x}-1(a\in R)\).

              \((\)Ⅰ\()\)讨论\(f(x)\)的单调性;

              \((\)Ⅱ\()\)证明:\({{\ln }^{2}}{{1}^{n}}+{{\ln }^{2}}{{2}^{n}}+\cdots +{{\ln }^{2}}{{n}^{n}} > \dfrac{{{(n-1)}^{4}}}{4n}(n\geqslant 2,n\in {{N}^{*}})\).

            • 5.

              若\(x > 0,y > 0\),且\(\dfrac{1}{2x+y}+\dfrac{1}{x+y}=2\),则\(4x+3y\)的最小值________.

            • 6. 设M=(-1)(-1)(-1)满足a+b+c=1(其中a>0,b>0,c>0),则M的取值范围是(  )
              A.[0,
              B.[,1)
              C.[1,8)
              D.[8,+∞)
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