已知抛物线C:x2=4y,过点D(0,2)的直线l交C于A,B两点,过点A,B分别作C的切线,两切线相交于点P.
(1)记直线PA,PB的斜率分别为k1,k2,证明
为定值;
(2)记△PAB的面积为S△PAB,求S△PAB的最小值.
(1)记直线PA,PB的斜率分别为k1,k2,证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b881044b5c73db6fcce110525741b02.png)
(2)记△PAB的面积为S△PAB,求S△PAB的最小值.
更新时间:2020-07-22 12:29:48
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【推荐1】在直角坐标系
中,抛物线
与直线
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(1)求抛物线C的方程;
(2)求
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【推荐2】如图所示,在平面直角坐标系
中,点
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(1)求
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上的点,且
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的面积的最小值.
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【推荐1】已知F是抛物线
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解题方法
【推荐2】已知圆
经过点
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为曲线
上一点.
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上异于
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