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[几何] 江苏2012解析几何题的背景

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郝酒 posted 2014-5-3 17:37 |Read mode
如图,在平面直角坐标系$xOy$中,椭圆$\frac{{{x}^{2}}}{{{a}^{2}}}+\frac{{{y}^{2}}}{{{b}^{2}}}=1\ (a>b>0)$的左、右焦点分别为${{F}_{1}}(-c,0),{{F}_{2}}(c,0)$.已知$(1,e)$和$\left( e,\frac{\sqrt{3}}{2} \right)$都在椭圆上,其中$e$为椭圆的离心率.
(1)求椭圆的方程;
(2)设A,B是椭圆上位于x轴上方的两点,且直线AF1与直线BF2平行,AF2与BF1交于点P.
(i)若$A{{F}_{1}}-B{{F}_{2}}=\frac{\sqrt{6}}{2}$,求直线AF1的斜率;
(ii)求证:$P{{F}_{1}}+P{{F}_{2}}$是定值.

感觉这道题出得好好啊。把椭圆的定义和原来相似形的结构结合起来。具体有没有挖掘呢?

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kuing posted 2014-5-3 17:39
见《数学空间》2012 年第 2 期 总第 9 期 P21

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其妙 posted 2014-5-3 19:12
kk还专门写了“play高考”的吧

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kuing posted 2014-5-3 19:47
kk还专门写了“play高考”的吧
其妙 发表于 2014-5-3 19:12
《数学空间》2012 年第 2 期 总第 9 期 那篇文章就是由 play... 里面再整理上去的啊。

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