Question 2
Let $\omega$ be the incircle of a fixed equilateral triangle $ABC$. A variable tangent line $\ell$ to $\omega$ meets the interiors of $BC,CA$ at $P,Q$, respectively. Choose $R$ with $PR=PA$ and $QR=QB$. Find all possible locations of $R$.
Proposed by Titu Andreescu, Waldemar Pompe. Evan Chen’s third-party compilation; source discussion https://aops.com/community/p15952801. Source video https://youtu.be/r7j0oRtpErA?t=1575.
Proposed by Titu Andreescu, Waldemar Pompe. Evan Chen’s third-party compilation; source discussion https://aops.com/community/p15952801. Source video https://youtu.be/r7j0oRtpErA?t=1575.