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            • 1. \(7\)、已知 \(f\)\(( \)\(x\)\()=\) \(x\)\({\,\!}^{2}-\cos \) \(x\),则 \(f\)\((0.6)\), \(f\)\((0)\), \(f\)\((-0.5)\)的大小关系是 \((\)  \()\)
              A.\(f\)\((0) < \) \(f\)\((0.6) < \) \(f\)\((-0.5)\)     
              B.\(f\)\((0) < \) \(f\)\((-0.5) < \) \(f\)\((0.6)\)
              C.\(f\)\((0.6) < \) \(f\)\((-0.5) < \) \(f\)\((0)\)     
              D.\(f\)\((-0.5) < \) \(f\)\((0) < \) \(f\)\((0.6)\)
            • 2.
              已知函数\(f(x)\)的部分图象如图,则\(f(x)\)的解析式可能为\((\)  \()\)
              A.\(f(x)=x\cos x-\sin x\)
              B.\(f(x)=x\sin x\)
              C.\(f(x)=x\cos x+\sin x\)
              D.\(f(x)=x\cos x\)
            • 3.

              已知定义在\(R\)上的偶函数\(f\left( x \right)\)满足\(f\left( x+4 \right)=f\left( x \right)\),且当\(0\leqslant x\leqslant 2\)时,\(f\left( x \right)=\min \left\{ -{{x}^{2}}+2x,2-x \right\}\),若方程\(f\left( x \right)-mx=0\)恰有两个根,则\(m\)的取值范围是

              A.\((-\infty ,-\dfrac{1}{3})\bigcup (\dfrac{1}{3},{+}\infty )\)
              B.\((-\infty ,-\dfrac{1}{3}]\bigcup [\dfrac{1}{3},{+}\infty )\) 
              C.\((-2,-\dfrac{1}{3})\bigcup (\dfrac{1}{3},2)\)
              D.\([-2,-\dfrac{1}{3}]\bigcup [\dfrac{1}{3},2]\)
            • 4.

              函数\(f(x)= \sqrt{3}\cos (3x-θ)-\sin (3x-θ)\)是奇函数,则\(\tan θ\)等于\((\)  \()\)

              A.\( \dfrac{ \sqrt{3}}{3}\)
              B.\(- \dfrac{ \sqrt{3}}{3}\)
              C.\( \sqrt{3}\)
              D.\(- \sqrt{3}\)
            • 5.

              已知函数\(f(x)\)是定义在\(R\)上的奇函数,且在区间\([0,+\infty )\)上\(3f(x)+x{f}{{{"}}}(x) > 0\)恒成立\(.\)若\(g(x)={{x}^{3}}f(x)\),令\(a=g({{\log }_{2}}\left( \dfrac{1}{e} \right))\),\(b=g({{\log }_{5}}2)\),\(c=g({e}^{- \frac{1}{2}}) \)则

              A.\(a < b < c\)
              B.\(b < c < a\)
              C.\(b < a < c\)
              D.\(c < b < a\)
            • 6.

              设函数\(f(x)={{x}^{3}}+x\),\(x\in R .\)若当\(0 < \theta < \dfrac{\pi }{2}\)时,不等式\(f(m\sin θ)+f(1-m) > 0\)恒成立,则实数\(m\)的取值范围是\((\)  \()\)

              A.\((\dfrac{1}{2},1]\)
              B.\((\dfrac{1}{2},1)\)
              C.\([1,+\infty )\)
              D.\((-\infty ,1]\)
            • 7.

              设函数\(f\left(x\right)=k{a}^{x}-{a}^{-x} \), \((a > 0\)且\(a\neq 1)\)是定义域为\(R\)的奇函数.

              \((\)Ⅰ\()\) 求\(k \)的值

              \((\)Ⅱ\()\)若\(f\left(1\right) > 0 \),试求不等式\(f\left({x}^{2}+2x\right)+f\left(x-4\right) > 0 \)的解集;

              \((\)Ⅲ\()\)若\(f\left(1\right)= \dfrac{3}{2} \),且\(g\left(x\right)={a}^{2x}+{a}^{-2x}-4f\left(x\right) \),求\(g\left(x\right) \)在\(\left(1,+∞\right) \)上的最小值。

            • 8.

              已知\(f\left( x \right)\)是定义在\(R\)上的奇函数,且当\(x\in \left( -\infty ,0 \right)\)时,不等式\(f\left( x \right)+x{{f}^{{{{"}}}}}\left( x \right) < 0\)成立,若\(a=\pi f\left( \pi \right),b=\left( -2 \right)f\left( -2 \right),c=f\left( 1 \right)\),则\(a,b,c\)的大小关系是  \((\)  \()\)

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

              设\(f\left(x\right) \)是定义在\(R\)上的偶函数,对任意\(x∈R \),都有\(f\left(x-2\right)=f\left(x+2\right) \)且当\(x∈\left[-2,0\right] \)时,\(f\left(x\right)={\left( \dfrac{1}{2}\right)}^{x}-1 \)若在区间\((-2,6] \)内关于\(x\)的方程\(f\left(x\right)-{\log }_{a}\left(x+2\right)=0\left(a > 1\right) \)恰有\(3\)个不同的实数根,则\(a\)的取值范围是\((\)    \()\)

              A.\(\left( \sqrt[3]{4},2\right) \)
              B.\(\left(2,+∞\right) \)
              C.\(\left(1, \sqrt[3]{4}\right) \)
              D.\((1,2)\)
            • 10.

              定义在\(\begin{cases} \dfrac{3}{4}{{m}^{2}}-3m+4=m \\ \dfrac{3}{4}{{n}^{2}}-3n+4=n \end{cases}\)上的增函数\(m=\dfrac{4}{3},n=4\),已知\(m,n\),若\(m=1,n=4\),则实数\(2{{x}_{2}}+\dfrac{a}{{{x}_{2}}}-1 > f{{({{x}_{1}})}_{\max }}\)的取值范围是\((\)   \()\)

              A.\(f{{({{x}_{1}})}_{\max }}=4,{{x}_{1}}\in [0,3]\)
              B.\(2{{x}_{2}}+\dfrac{a}{{{x}_{2}}} > 5\)
              C.\([1,2]\)
              D.\(a > -2{{x}_{2}}^{2}+5{{x}_{2}},{{x}_{2}}\in [1,2]\)
            0/40

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