优优班--学霸训练营 > 知识点挑题
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            • 1.

              已知\(F\)为抛物线\({{y}^{2}}=4x\)的焦点,\(P\)是抛物线上的一个动点,点\(A\)的坐标为\(\left( 5,3 \right)\),则\(\left| PA \right|+\left| PF \right|\)的最小值为\((\)     \()\)

              A.\(5\)           
              B.\(6\)          
              C.\(7\)           
              D.\(8\)
            • 2. 双曲线\(C\):\( \dfrac {x^{2}}{a^{2}}- \dfrac {y^{2}}{b^{2}}=1(a > 0,b > 0)\)的离心率为\( \sqrt {2}\),双曲线\(C\)的渐近线与抛物线\(y^{2}=2px(p > 0)\)交于\(A\),\(B\)两点,\(\triangle OAB(O\)为坐标原点\()\)的面积为\(4\),则抛物线的方程为\((\)  \()\)
              A.\(y^{2}=8x\)
              B.\(y^{2}=4x\)
              C.\(y^{2}=2x\)
              D.\(y^{2}=4 \sqrt {3}x\)
            • 3.

              若抛物线\({y}^{2}=8x \)上一点\(P\)到其焦点的距离为\(9\),则点\(P\)的坐标为\((\)   \()\)。

              A.\(\left(7,± \sqrt{14}\right) \)
              B.\(\left(14,± \sqrt{14}\right) \)
              C.\(\left(7,±2 \sqrt{14}\right) \)
              D.\(\left(-7,±2 \sqrt{14}\right) \)
            • 4.

              以坐标轴为对称轴,以原点为顶点且过圆\({x}^{2}+{y}^{2}-2x+6y+9=0 \)的圆心的抛物线的方程是(    )

              A.\(y=3{x}^{2} \)或\(y=-3{x}^{2} \)
              B.\(y=3{x}^{2} \)
              C.\({y}^{2}=-9x \)或\(y=3{x}^{2} \)
              D.\(y=-3{x}^{2} \)或\({y}^{2}=9x \)
            • 5.

              设\(AB\)为过抛物线\({{y}^{2}}=2px(p > 0)\)的焦点的弦,则\(\left| AB \right|\)的最小值为(    )

              A.\(\dfrac{p}{2}\)
              B.\(p\)
              C.\(2p\)
              D.无法确定
            • 6.

              若点\(A\)的坐标为\((3,2)\),\(F\)是抛物线\({{y}^{2}}=2x\)的焦点,点\(M\)在抛物线上移动时,使\(\left| MF \right|+\left| MA \right|\)取得最小值的\(M\)的坐标为(    ).

              A.\(\left( 0,0 \right)\)
              B.\(\left( \dfrac{1}{2},1 \right)\)
              C.\(\left( 1,\sqrt{2} \right)\)
              D.\(\left( 2,2 \right)\)
            • 7.

              若抛物线\({{y}^{2}}=8x\)上一点\(P\)到其焦点的距离为\(9\),则点\(P\)的坐标为

              A.\((7,\pm \sqrt{14})\)
              B.\((14,\pm \sqrt{14})\)
              C.\((7,\pm 2\sqrt{14})\)
              D.\((-7,\pm 2\sqrt{14})\)
            • 8.

              已知圆\(C_{1}\):\(x^{2}+(y-2)^{2}=4\),抛物线\(C_{2}\):\(y^{2}=2px(p > 0)\),\(C_{1}\)与\(C_{2}\)相交于\(A.B\)两点,且\(|AB|=\dfrac{8\sqrt{5}}{5}\),则抛物线\(C_{2}\)的方程为

              A.\({{y}^{2}}=\dfrac{8}{5}x\)
              B.\({{y}^{2}}=\dfrac{16}{5}x\)
              C.\({{y}^{2}}=\dfrac{32}{5}x\)
              D.\({{y}^{2}}=\dfrac{64}{5}x\)
            • 9.
              探照灯反射镜的轴截面是抛物线的一部分,光源位于抛物线的焦点处,已知灯口的直径为\(60 cm\),灯深\(40 cm\),则抛物线的标准方程可能是(    )
              A.\(y\)\({\,\!}^{2}= \dfrac{25}{4}\) \(x\)                         
              B.\(y\)\({\,\!}^{2}= \dfrac{45}{4}\) \(x\)
              C.\(x\)\({\,\!}^{2}=- \dfrac{45}{2}\) \(y\)                     
              D.\(x\)\({\,\!}^{2}=- \dfrac{45}{4}\) \(y\)
            • 10.
              顶点在原点,对称轴为坐标轴,且过点\(P(-4,-2)\)的抛物线的标准方程是\((\)  \()\)
              A.\(y^{2}=-x\)
              B.\(x^{2}=-8y\)
              C.\(y^{2}=-8x\)或\(x^{2}=-y\)
              D.\(y^{2}=-x\)或\(x^{2}=-8y\)
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