Inscribed angles: around the orthocenter
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Timecodes!
00:00:00 The last webinar on inscribed angles! Orthocenter.
00:00:35 After this intensive course, will I be able to solve any problem about inscribed angles?
00:01:33 Orthocenter. Definition.
00:02:15 Problem 1. How to prove inscription without using a picture?
00:07:14 We drew just 3 altitudes and got 6 inscribed quadrilaterals!
00:08:08 Problem 2. About points H and O. A fact worth committing to memory.
00:13:04 Problem 3. Vsesib - 2016. How does symmetry with respect to the bisector work?
00:30:59 Problem 4. New useful points on the circumscribed circle.
00:39:51 Problem 5. Let's make a construction that suggests itself.
00:55:55 Problem 6. Orthotriangle. Simple angle counting.
01:00:16 Problem 7. OMMO - 2018. Unfolding the picture using accumulated knowledge