优优班--学霸训练营 > 知识点挑题
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            • 1.
              已知函数\(f(x)= \begin{cases} \overset{2^{x},x\geqslant 4}{f(x+1)\;\;,x < 4}\end{cases}\),则\(f(2+\log _{2}3)\)的值为\((\)  \()\)
              A.\(24\)
              B.\(16\)
              C.\(12\)
              D.\(8\)
            • 2.

              已知函数\(f(x)(x∈R)\)满足,\(f(-x)=2-f(x)\),若函数\(y=\dfrac{x+1}{x}\)与\(y=f(x)\),图像的交点为\((x_{1},y_{1})\),\((x_{2},y_{2})\),\(…(x_{m},y_{m}).\)则\(\sum\limits_{i=1}^{m}{({{x}_{1}}+{{y}_{1}})}\)等于

              A.\(0\)
              B.\(m\)
              C.\(2m\)
              D.\(4m\)
            • 3.

              \((1)\)在等腰\(\Delta ABC\)中,\(AB=AC\),\(BC=6\),点\(D\)为边\(BC\)的中心,则\(\overrightarrow{AB}\cdot \overrightarrow{BD}=\)_________.

              \((2)\)设\(x\),\(y\)满足约束条件\(\begin{cases} & 2x+y-1\leqslant 0 \\ & x+2y+1\geqslant 0 \\ & x-y+1\geqslant 0 \end{cases}\),则\(z=2x-3y\)的最大值为_________.

              \((3)\)设函数\(f(x)(m\in R)\)满足\(f(x-\pi )=f(x)-\sin x\),当\(-\pi < x\leqslant 0\)时,则\(f(\dfrac{2018\pi }{3})=\)_________\(..\)

              \((4)\)椭圆的左、右焦点分别为\({F}_{1},{F}_{2} \),弦\(AB\)过\({F}_{1} \),若\(∆AB{F}_{2} \)的内切\(\dfrac{{{x}^{2}}}{36}+\dfrac{{{y}^{2}}}{20}=1\)圆周长为\(2\pi \),\(A\),\(B\)两点的坐标分别为\(\left({x}_{1},{y}_{1}\right) \)和\(\left({x}_{2},{y}_{2}\right) \),则\(\left| {{y}_{2}}-{{y}_{1}} \right|=\)___________.

            • 4.
              若\(x\),\(y∈R\),且\(f(x+y)=f(x)+f(y)\),则函数\(f(x)(\)  \()\)
              A.\(f(0)=0\)且\(f(x)\)为奇函数
              B.\(f(0)=0\)且\(f(x)\)为偶函数
              C.\(f(x)\)为增函数且为奇函数
              D.\(f(x)\)为增函数且为偶函数
            • 5.
              定义在\(R\)上的偶函数满足\(f( \dfrac {3}{2}+x)=f( \dfrac {3}{2}-x)\)且\(f(-1)=1\),\(f(0)=-2\),则\(f(1)+f(2)+f(3)+…+f(2014)\)的值为\((\)  \()\)
              A.\(1\)
              B.\(-2\)
              C.\(2\)
              D.\(0\)
            • 6.
              函数\(f(x)\)满足对定义域内的任意\(x\),都有\(f(x+2)+f(x) < 2f(x+1)\),则函数\(f(x)\)可以是\((\)  \()\)
              A.\(f(x)=2x+1\)
              B.\(f(x)=x^{2}-2x\)
              C.\(f(x)=e^{x}\)
              D.\(f(x)=\ln x\)
            • 7.

              已知\(f\left( x+1 \right)=\dfrac{2f\left( x \right)}{f\left( x \right)+2}\),\(f\left( 1 \right)=1(x\in N*)\),猜想\(f\left( x \right)\)的表达式为\((\)  \()\)

              A.\(f\left( x \right)=\dfrac{2}{x+1}\)
              B.\(f\left( x \right)=\dfrac{4}{{{2}^{x}}+2}\)
              C.\(f\left( x \right)=\dfrac{1}{x+1}\)
              D.\(f\left( x \right)=\dfrac{2}{2x+1}\)
            • 8.
              若\(f(x)\)是定义在\((0,+∞)\)上的增函数,且\(f( \dfrac {x}{y})=f(x)-f(y)\).
              \((\)Ⅰ\()\)求\(f(1)\)的值;
              \((\)Ⅱ\()\)解不等式:\(f(x-1) < 0\).
            • 9.

              \(12\)\(f\)\((\)\(x\)\()\)与\(g\)\((\)\(x\)\()\)是定义在同一区间\([\)\(a\)\(b\)\(]\)上的两个函数,若函数\(y=f\)\((\)\(x\)\()\)\(-g\)\((\)\(x\)\()\)在\(x\)\(∈[\)\(a\)\(b\)\(]\)上有两个不同的零点,则称\(f\)\((\)\(x\)\()\)和\(g\)\((\)\(x\)\()\)在\([\)\(a\)\(b\)\(]\)上是“关联函数”,区间\([\)\(a\)\(b\)\(]\)称为“关联区间”\(f\)\((\)\(x\)\()\)\(=x\)\({\,\!}^{2}\)\(-\)\(3\)\(x+\)\(4\)与\(g\)\((\)\(x\)\()\)\(=\)\(2\)\(x+m\)在\([0,3]\)上是“关联函数”,则\(m\)的取值范围为 \(.\) 

            • 10. 若函数\(f(x)\)具有性质:\(f( \dfrac {1}{x})=-f(x)\),则称\(f(x)\)是满足“倒负”变换的函数\(.\)下列四个函数:
              \(①f(x)=\log _{a}x(a > 0\)且\(a\neq 1)\);        
              \(②f(x)=a^{x}(a > 0\)且\(a\neq 1)\);
              \(③y=x- \dfrac {1}{x}\);                      
               \(④f(x)= \begin{cases} x\;\;\;,(0 < x < 1) \\ 0,(x=1) \\ - \dfrac {1}{x}\;\;,(x > 1)\end{cases}\).
              其中,满足“倒负”变换的所有函数的序号是 ______ .
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