A Focal Chord and Its Shadows
Difficulty: Medium · Topics: Geometry, Conic Sections, Parabola
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A line through the focus F of the parabola y^2=12x meets the parabola at the two points A and B. From A and B, perpendiculars are dropped to the directrix l, with feet C and D respectively.
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If overlineBD=5, what is the length of the segment AC?
y^2=12x parabolaning F fokusidan o‘tuvchi to‘g‘ri chiziq parabolani ikki A va B nuqtada kesadi. A va B dan l direktrisaga perpendikulyarlar tushirilgan, ularning asoslari mos ravishda C va D.
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Agar overlineBD=5 bo‘lsa, AC kesma uzunligi qancha?