Xuming's Synthetic Geometry Group- Mehul's Proposal

Q1)Let ABC be a triangle in which ∠A = 60∘60^ {\circ} Let BE and CF be the bisectors of the angles ∠B and ∠C with E on AC and F on AB. Let M be the reflection of A in the line EF. Prove that M lies on BC.

Q2) Let ABCD be a convex quadrilateral. Let E, F, G, H be midpoints of AB, BC, CD, DA respectively. If AC, BD, EG, FH concur at a point O, prove that ABCD is a parallelogram.

Q3) (Extra one) Let ABC be an acute angled scalene triangle with circumcenter O and orthocenter H. If M is the midpoint of BC, then show that AO and HM intersect at the circumcircle of ABC.

(Problems taken from previous year RMO papers)

Note by Mehul Arora
5 years, 8 months ago

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@Calvin Lin @Xuming Liang Hope you like these! :)

Mehul Arora - 5 years, 8 months ago
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