Section
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Sketches
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1
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The four classical
triangle centers: centroid, circumcenter, incenter, orthocenter
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1
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More triangle
centers: Gergonne point, Feuerbach point, Nagel point
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2.1
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The line L(t)
cutting equal intercepts on AC and AB
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| 2.2,3 |
Parabola tangent
to the sidelines of a triangle
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2.4,5,6
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The envelope
of L(t): inscribed parabola with focus the midpoint of arc BAC
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2.7
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The Simson lines
of the midpoints of arc BAC, CBA, ACB concur at the incenter of the medial
triangle
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3.1
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Triangle bounded
by La(t), Lb(t) and Lc(t)
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3.2,3
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Locus of perspector
of triangle bounded by La (t), Lb (t), Lc
(t) |
3.4
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Orthology of
ABC and the triangle bounded by La (s),
Lb (s), Lc (s) |
4
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The triangle
bounded by L'a(t), L'b(t), L'c(t)
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5
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The lines La(a),
Lb(b), Lc(c)
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| 6 |
The lines La(-a),
Lb(-b), Lc(-c) and related triangles
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| 7 |
The lines La(s-a), Lb(s-b), Lc(s-c)
and the extouch triangle |