MathDB

2010.89.3

Part of Kyiv City MO Juniors Round2 2010+ geometry

Problems(1)

angle chasing, incenters, 30^o in acute (2010 Kyiv City MO Round2 8.3 9.3)

Source:

8/2/2020
In the acute-angled triangle ABCABC the angle∠B=30o \angle B = 30^o, point HH is the intersection point of its altitudes. Denote by O1,O2O_1, O_2 the centers of circles inscribed in triangles ABH,CBHABH ,CBH respectively. Find the degree of the angle between the lines AO2AO_2 and CO1CO_1.
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