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MathNet 2016-part-05 — 184 problems (EN–VI) Question 167

Math Olympiad Vault · MathNet 2016-part-05 — 184 problems (EN–VI)

Question 167

The inscribed circle of triangle $ABC$, with centre $I$, touches sides $BC$, $CA$ and $AB$ at $D$, $E$ and $F$, respectively. Let $P$ be a point, on the same side of $FE$ as $A$, for which $\angle PFE = \angle BCA$ and $\angle PEF = \angle ABC$. Prove that $P$, $I$ and $D$ lie on a straight line.