30 สิงหาคม 2013, 21:00
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ลมปราณคุ้มครองร่าง
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วันที่สมัครสมาชิก: 28 พฤศจิกายน 2012
ข้อความ: 295
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Pascal's Theorem
อ้างอิง:
Pascal's Theorem:
degenerate case of Pascal's Theorem (four points) is interesting; given points ABCD on a conic Γ, the intersection of alternate sides, AB ∩ CD, BC ∩ DA, together with the intersection of tangents at opposite vertices (A, C) and (B, D) are collinear in four points; the tangents being degenerate 'sides', taken at two possible positions on the 'hexagon' and the corresponding Pascal Line sharing either degenerate intersection. This can be proven independently using a property of pole-polar. If the conic is a circle, then another degenerate case tells us that for a triangle, the three points that appear as the intersection of a side line with the corresponding side line of the Gergonne triangle, are collinear.
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อยากได้โจทย์เกี่ยวกับ Pascal's Theorem ครับ
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