优优班--学霸训练营 > 知识点挑题
全部资源
          排序:
          最新 浏览

          50条信息

            • 1.

              设直线\(l\)的方程为\((a{+}1)x{+}y{+}2{-}a{=}0\),\(a{∈}R\).

              \((1)\)若\(l\)在两坐标轴上的截距相等,求\(l\)的方程;

              \((2)\)若\(l\)与两坐标轴围成的三角形的面积为\(6\),求\(a\)的值.

            • 2.

              将一颗骰子投掷两次,第一次出现的点数记为\(a\),第二次出现的点数记为\(b\),设两条直线\(l_{1}:ax+by=2\), \(l_{2}:x+2y=2\), \(l_{1}\)与\(l_{2}\)平行的概率为\(p_{1}\),相交的概率为\(p_{2}\),则\(p_{2}-p_{1}\)的大小为(    )

              A.\( \dfrac{31}{36} \)
              B.\( \dfrac{5}{6} \)
              C.\(- \dfrac{5}{6} \)
              D.\(- \dfrac{31}{36} \)
            • 3.

              直线过点\(P\left( \dfrac{4}{3},2 \right)\)且与\(x\)轴、\(y\)轴的正半轴分别交于\(A\),\(B\)两点,\(O\)为坐标原点,是否存在这样的直线同时满足条件:

              \((i)\triangle AOB\)的周长为\(12\);

              \((ii)\triangle AOB\)的面积为\(6.\)若存在,求出直线的方程;若不存在,请说明理由.

            • 4.
              已知直线\(l_{1}\):\(y=ax-2a+5\)过定点\(A\),则点\(A\)到直线\(l\):\(x-2y+3=0\)的距离为\((\)  \()\)
              A.\(2 \sqrt {5}\)
              B.\( \dfrac { \sqrt {5}}{5}\)
              C.\( \sqrt {5}\)
              D.\( \dfrac {2 \sqrt {5}}{5}\)
            • 5.

              已知实数\(x\)\(y\)满足\(\begin{cases}x-3y-6\leqslant 0, \\ y\leqslant 2x+4, \\ 2x+3y-12\leqslant 0,\end{cases}\)直线\((1+\)\(λ\)\()\)\(x\)\(+(1-2\)\(λ\)\()\)\(y\)\(+3\)\(λ\)\(-12=0 (\)\(λ\)\(∈R)\)过定点\(A\)\((\)\(x\)\({\,\!}_{0}\),\(y\)\({\,\!}_{0})\),则\(z\)\(= \dfrac{y-y_{0}}{x-x_{0}}\)的取值范围为(    )

              A.\((-∞, \dfrac{1}{5}]∪[7,+∞)\)   
              B.\([ \dfrac{1}{5},7]\)     
              C.\((-∞, \dfrac{1}{7}]∪[5,+∞)\)     
              D.\([ \dfrac{1}{7},5]\)
            • 6.

              \((1)\)点\(P(2,1)\)关于直线\(x-y+1=0\)的对称点\(Q\)的坐标为_______________.


              \((2)\)已知\(\triangle ABC\)的一个内角为\(120^{\circ}\),且三边长构成公差为\(2\)的等差数列,则\(\triangle ABC\)的面积为____________.


              \((3)\)已知\(\left\{{a}_{n}\right\} \)是公比为\(q\)的等比数列,\({{S}_{n}}\)是\(\left\{{a}_{n}\right\} \)的前\(n\)项和,且\(9{{S}_{3}}={{S}_{6}}\),若正数\(a,b\)满足:\(\dfrac{2}{a}+\dfrac{4}{b}=q\),则\(\dfrac{2}{a-1}+\dfrac{1}{b-2}\)的最小值为___________.


              \((4)\)已知函数\(f(x)=\ln \dfrac{1+x}{1-x}+\sin x\),则关于\(a\)的不等式\(f(a-2)+f({{a}^{2}}-4) < 0\)的解集是_________.

            • 7.

              设直线\(l\)的方程为\((a+1)x+y-2-a=0\quad (a\in R)\).

              \((1)\)若直线\(l\)在两坐标轴上的截距相等,求直线\(l\)的方程;

              \((2)\)若\(a > -1\),直线\(l\)与\(x\),\(y\)轴分别交于\(M\),\(N\)两点,\(O\)为坐标原点,求\(\triangle OMN\)面积取最小值时,直线\(l\)的方程.

            • 8.

              \((1)\)若\(\tan \alpha =3\),则\(\dfrac{\sin 2\alpha }{{{\cos }^{2}}\alpha }\)的值为____________.

              \((2)\)已知直线\(y=2x+1\)与曲线\(y={{x}^{3}}+ax+b\)相切于点\((1,3)\),则实数\(b\)的值为______.

              \((3)\)已知过定点\(A\)的直线\(x+my=0\)与过定点\(B\)的直线\(mx-y-m+3=0\)相交于点\(P\),则\(\left| PA \right|+\left| PB \right|\)的最大值是______________.

              \((4)\)已知函数\(f(x)=1-\dfrac{m{{e}^{x}}}{{{x}^{2}}+x+1}\),若存在唯一的正整数\({{x}_{0}}\),使得\(f({{x}_{0}})\geqslant 0\),则实数\(m\)的取值范围___       

            • 9.

              \((1)\)若直线\(ax+2y-6=0\)与\(x+(a-1)y-(a^{2}-1)=0\)平行,则它们之间的距离为________.

              \((2)\)已知点\(A(3,2)\)和\(B(-1,4)\)到直线\(ax+y+1=0\)的距离相等,则\(a\)的值为________.

              \((3)\)将一张坐标纸折叠一次,使得点\((0,2)\)与点\((4,0)\)重合,点\((7,3)\)与点\((m,n)\)重合,则\(m+n=\)______.

              \((4)\)过点\((1, \sqrt{2})\)的直线\(l\)将圆\((x-2)^{2}+y^{2}=4\)分成两段弧,当劣弧所对的圆心角最小时,直线\(l\)的斜率\(k=\)________.

            • 10.
              如图,已知\(A(4,0)\)、\(B(0,4)\),从点\(P(2,0)\)射出的光线经直线\(AB\)反向后再射到直线\(OB\)上,最后经直线\(OB\)反射后又回到\(P\)点,则光线所经过的路程是\((\)  \()\)
              A.\(2 \sqrt {10}\)
              B.\(6\)
              C.\(3 \sqrt {3}\)
              D.\(2 \sqrt {5}\)
            0/40

            进入组卷