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            • 1.

              已知奇函数\(f(x)=\begin{cases} 3^{x}\mathrm{{-}}a\mathrm{(}x{\geqslant }0\mathrm{){,}} \\ g\mathrm{(}x\mathrm{)(}x{ < }0\mathrm{){,}} \end{cases}\)则\(f(-2)\)的值为____\(.\) 

            • 2.

              已知函数\(f(x)=\begin{cases} & \log \dfrac{1}{2}x,x > 0, \\ & \cos x,x\leqslant 0, \end{cases}\)则\(f\left( f\left( -\dfrac{\pi }{3} \right) \right)=\)________

            • 3.

              设定义在\(R\)上的奇函数\(y=f(x)\),满足对任意\(t∈R\)都有\(f(t)=f(1-t)\),且当\(x∈[0,\dfrac{1}{2}]\)时,\(f(x)=-x^{2}\),则\(f(3)+f\left( \mathrm{{-}}\dfrac{3}{2} \right)\)的值等于 \((\)  \()\)

              A.\(-\dfrac{1}{2}\)
              B.\(-\dfrac{1}{3}\)
              C.\(-\dfrac{1}{4}\)
              D.\(-\dfrac{1}{5}\)
            • 4.

              已知函数\(f(x)=\begin{cases}1-\left|x-1\right|,x\leqslant 2 \\ {e}^{x-2}\left(-{x}^{2}+8x-12\right),x > 2\end{cases} \)若在区间\((1,+∞)\)上存在\(n(n\geqslant 2)\)个不同的数\(x_{1}\),\(x_{2}\),\(x_{3}\),\(…\),\(x_{n}\),使得\(\dfrac{f({{x}_{1}})}{{{x}_{1}}}=\dfrac{f({{x}_{2}})}{{{x}_{2}}}=…=\dfrac{f({{x}_{n}})}{{{x}_{n}}}\)成立,则\(n\)的取值集合是   (    )

              A.\(\{2,3,4,5\}\)
              B.\(\{2,3\}\)
              C.\(\{2,3,5\}\)
              D.\(\{2,3,4\}\)
            • 5.

              已知在\((0,+∞)\)上函数\(f(x)=\begin{cases} -2,0 < x < 1 \\ 1,x\geqslant 1 \end{cases}\),则不等式\(\log _{2}x-(\log _{ \frac{1}{4}}4x-1)·f(\log _{3}x+1)\leqslant 5\)的解集为\((\)  \()\)

              A.\(( \dfrac{1}{3},1)\)                            
              B.\([1,4]\)

              C.\(( \dfrac{1}{3},4]\)                            
              D.\([1,+∞)\)
            • 6.

              已知函数\(f(x)=\begin{cases} 2^{x+1},x\leqslant 0 \\ 1-\log _{2}x,x > 0 \end{cases}\),则\(f(f(3))=(\)  \()\)

              A.\( \dfrac{4}{3}\)                                     
              B.\( \dfrac{2}{3}\)

              C.\(- \dfrac{4}{3}\)                               
              D.\(-3\)
            • 7.
              已知函数\(f(x)= \begin{cases} 2^{-x}-1,x\leqslant 0 \\ -x^{2}+x,x > 0\end{cases}\),则关于\(x\)的不等式\(f[f(x)]\leqslant 3\)的解集为 ______ .
            • 8.

              已知函数\(f(x)=\begin{cases} e^{x},x\geqslant 0 \\ ax,x < 0 \end{cases}\),若方程\(f(-x)=f(x)\)有五个不同的根,则实数\(a\)的取值范围为\((\)  \()\)

              A.\((-∞,-e)\)                             
              B.\((-∞,-1)\)

              C.\((1,+∞)\)                                
              D.\((e,+∞)\)
            • 9.

              已知函数\(f(x)=\begin{cases} e^{x}-1,x > 0 \\ \dfrac{3}{2}x+1,x\leqslant 0 \end{cases}.\)若\(m < n\),且\(f(m)=f(n)\),求\(n-m\)的取值范围.

            • 10.

              \((1)①\dfrac{2\sin {{46}^{\circ }}-\sqrt{3}\cos {{74}^{\circ }}}{\cos {{16}^{\circ }}}=\) _________    \(\_\).

              \(②\sin 42{}^\circ \cos 18{}^\circ -\cos 138{}^\circ \cos 72{}^\circ =\)________    __.

              \((2)①\)设函数\(f(x)=\begin{cases} & x,x < 1 \\ & {{x}^{3}}-\dfrac{1}{x}+1,x\geqslant 1 \\ \end{cases}\),则不等式\(f(6-{{x}^{2}}) > f\left( x \right)\)的解集为____       \(\_\)

              \(②\)设函数\(f(x)=\begin{cases} & x,x < 1 \\ & {{x}^{3}}-\dfrac{1}{x}+1,x\geqslant 1 \\ \end{cases}\),则\(f(\dfrac{1}{f(2)}) =\)__________

              \((3)①\)将函数\(f(x)=\sin (3x+ \dfrac{π}{4}) \)图像向左平移\(m(m > 0)\)个单位后所对应的函数是偶函数,则\(m\)的最小值是             

              \(②\)函数\(f(x)=\sin (3x+ \dfrac{π}{4}) \)的最小正周期为              

              \((4)①\)等腰\(\Delta ABC\)的顶角\(A=\dfrac{2\pi }{3}\),\(\left| BC \right|=2\sqrt{3}\),以\(A\)为圆心,\(1\)为半径作圆,\(PQ\)为直径,则\(\overrightarrow{BP}\cdot \overrightarrow{CQ}\)的最大值为\(\_\)___   ______.

              \(②\)等腰\(\Delta ABC\)的顶角\(A=\dfrac{2\pi }{3}\),\(\left| BC \right|=2\sqrt{3}\),则\(\overrightarrow{BA}\bullet \overrightarrow{AC}=\)_____    _____.

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