优优班--学霸训练营 > 知识点挑题
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            • 1.
              过抛物线\(y^{2}=4x\)焦点的直线交抛物线于\(A\)、\(B\)两点,若\(|AB|=10\),则\(AB\)的中点\(P\)到\(y\)轴的距离等于 ______ .
            • 2.

              已知抛物线\(y=ax^{2}\)上点\(P(x_{0},2)\)到焦点的距离为\(3\),则点\(P\)到\(y\)轴的距离是\((\)  \()\)
              A.\( \dfrac { \sqrt {2}}{2}\)
              B.\(1\)
              C.\(2 \sqrt {2}\)
              D.\(2\)
            • 3.
              抛物线\(y=2x^{2}\)上有一点\(P\),它到\(A(2,10)\)距离与它到焦点距离之和最小时,点\(P\)坐标是\((\)  \()\)
              A.\(( \sqrt {5},10)\)
              B.\(( \sqrt {5},20)\)
              C.\((2,8)\)
              D.\((1,2)\)
            • 4.
              从抛物线\(x^{2}=4y\)的准线\(l\)上一点\(P\)引抛物线的两条切线\(PA\)、\(PB\),且\(A\)、\(B\)为切点,若直线\(AB\)的倾斜角为\( \dfrac {π}{6}\),则\(P\)点的横坐标为 ______ .
            • 5.
              已知抛物线\(y^{2}=4x\)的焦点为\(F\),\(A\)、\(B\)为抛物线上两点,若\( \overrightarrow{AF}=3 \overrightarrow{FB}\),\(O\)为坐标原点,则\(\triangle AOB\)的面积为\((\)  \()\)
              A.\( \dfrac { \sqrt {3}}{3}\)
              B.\( \dfrac {8 \sqrt {3}}{3}\)
              C.\( \dfrac {4 \sqrt {3}}{3}\)
              D.\( \dfrac {2 \sqrt {3}}{3}\)
            • 6.
              已知抛物线\(C\):\(y^{2}=8x\)的焦点为\(F\),准线为\(l\),\(P\)是\(l\)上一点,\(Q\)是直线\(PF\)与\(C\)的一个交点,若\( \overrightarrow{FP}=3 \overrightarrow{FQ}\),则\(|QF|=(\)  \()\)
              A.\( \dfrac {8}{3}\)
              B.\( \dfrac {5}{2}\)
              C.\(3\)
              D.\(2\)
            • 7.
              已知抛物线\(C\):\(y^{2}=2px\)过点\(P(1,1).\)过点\((0, \dfrac {1}{2})\)作直线\(l\)与抛物线\(C\)交于不同的两点\(M\),\(N\),过点\(M\)作\(x\)轴的垂线分别与直线\(OP\)、\(ON\)交于点\(A\),\(B\),其中\(O\)为原点.
              \((1)\)求抛物线\(C\)的方程,并求其焦点坐标和准线方程;
              \((2)\)求证:\(A\)为线段\(BM\)的中点.
            • 8.
              已知抛物线\(C\):\(y^{2}=4x\)的焦点为\(F\),过点\(F\)分别作两条直线\(l_{1}\),\(l_{2}\),直线\(l_{1}\)与抛物线\(C\)交于\(A\)、\(B\)两点,直线\(l_{2}\)与抛物线\(C\)交于\(D\)、\(E\)两点,若\(l_{1}\)与\(l_{2}\)的斜率的平方和为\(1\),则\(|AB|+|DE|\)的最小值为\((\)  \()\)
              A.\(16\)
              B.\(20\)
              C.\(24\)
              D.\(32\)
            • 9.
              与直线\(4x-y+3=0\)平行的抛物线\(y=2x^{2}\)的切线方程是\((\)  \()\)
              A.\(4x-y+1=0\)
              B.\(4x-y-1=0\)
              C.\(4x-y-2=0\)
              D.\(4x-y+2=0\)
            • 10.
              已知抛物线\(C_{1}\):\(y^{2}=2px(p > 0)\)的焦点为\(F\),准线与\(x\)轴的交点为\(E\),线段\(EF\)被双曲线\(C_{2}\):\( \dfrac {x^{2}}{a^{2}}- \dfrac {y^{2}}{b^{2}}=1(a > 0,b > 0)\)的顶点三等分,且两曲线\(C_{1}\),\(C_{2}\)的交点连线过曲线\(C_{1}\)的焦点\(F\),曲线\(C_{2}\)的焦距为\(2 \sqrt {11}\),则曲线\(C_{2}\)的离心率为\((\)  \()\)
              A.\( \sqrt {2}\)
              B.\( \dfrac {3 \sqrt {2}}{2}\)
              C.\( \dfrac { \sqrt {11}}{3}\)
              D.\( \dfrac { \sqrt {22}}{2}\)
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