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[几何] 今日研究的一个解几题

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等待hxh Posted 2014-4-10 22:51 |Read mode
Last edited by hbghlyj 2025-5-3 02:21$P$ 为圆 $O: x^2+y^2=1$ 上一动点,圆 $O$ 在点 $P$ 处切线交椭圆 $C: \frac{x^2}{3}+\frac{y^2}{2}=1$于 $A, C$ 两点,再过点 $A, C$ 作圆 $O$ 的另一条切线分别交椭圆 $C$ 于点 $B, D$ 两点,过点 $B, D$ 作圆 $O$ 的另一条切线相交于点 $Q$,求动点 $Q$ 的轨迹方程\[
\frac{x^2}{\left(\frac{1249}{1151}\right)^2} + \frac{y^2}{\left(\frac{1201}{1151}\right)^2} = 1
\]

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1+1=? Posted 2025-5-3 09:54 From mobile phone
Last edited by hbghlyj 2025-5-3 12:25提供一点思路,利用单位圆切线坐标系$$
\left(\frac{1-u v}{1+u v}, \frac{u+v}{1+u v}\right)
$$省去了计算切线与椭圆交点的步骤

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